Compatible or Narrow Shank?
Compatible Shank Couplers
Prototype Couplers compatible shank couplers feature a shank that allows them to be a drop-in upgrades for the traditional knuckle couplers included on most HO scale cars and locomotives.
Narrow Shank Couplers for HO and HOn3
These couplers feature the same coupler head design used in the compatible shank couplers. However, these have a shank narrow enough to be used in true scale size draft gear boxes.
Die Cast, Hybrid, or Investment Cast?
Die Cast Couplers
Our die cast couplers utilize the exact same tooling Sergent Enginnering used for decades. This means that our die cast couplers are 100% identical to a Sergent die cast coupler. You will notice that the castings are very consistant and uniform with little clean up required by the end user for a perfect fit. These couplers also have the same short comings as a original Sergent coupler, notably the alignment pin goes through the shank and can be seen from the top of the coupler. Our investment cast couplers remedy this.
Hybrid Couplers
These couplers are a mix between our die cast couplers and our investment cast couplers. These are primarily offered where a die cast part would be too costly to make. The shanks are all investment cast parts. The knuckle and bottom cover are die cast. These potentially need a small amount of clean up on the shank. This is how Sergent Engineering made their specialty couplers like their SEC87K. We continue this tradition with our hybrid couplers. If you want orginal Sergent style specialty couplers than these are the style for you. These couplers also have the alignment pin going through the shank and viewable from the top of the coupler.
Investment Cast Couplers
Our investment cast couplers use the same techniques used by Sergent Engineering to manufacture their tightlock couplers. We use a investment cast shank and bottom cover with a die cast knuckle to ensure consistant operation. We tried using investment cast knuckles but could not get consistant results that we were happy with. All investment cast couplers boast increased prototypical accuracy by eliminating the alignment pin going through the entire shank. Now this pin only goes half way through the shank. This allows for alignment still but keeps the top smooth and free of any holes that needs filling. You'll notice that the investment castings aren't as clean those that come from the die casting process. What this means in terms of assembling couplers from investment cast parts is that you'll have to pay more attention detail than you do with die cast parts. This isn't a huge deal, but do expect to spend more time assembling and checking these couplers than you do with the EC87KD and EN87KD couplers. Investment casting is a multi-day process and is very labor intensive on me. I have strict times I need to do specific actions for this process. Investment casting also is not cheap. Material gets consumed in the form of our 3D printed resin masters, and the investment powder required to make a mold of the masters. These materials are expensive and if we have a bad run are wasted. Prices reflect what we feel is fair for our time and labor.
Die Cast Couplers
| Picture | Part # | Description | Price | Status | Buy Now |
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EC87KD | 6 Easy-to-Assemble Die Cast AAR Type E Couplers with compatible shank (If you're new to our couplers and wonder what you need to try first -- this is it!) Original Sergent Style. | $20.00 | In Stock | |
| EC87KB | 100 Easy-to-Assemble Die Cast AAR Type E Couplers with compatible shank. Original Serget Style. | $150.00 | Pre-Order | ||
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SBEC87KD | 6 Easy-to-Assemble Die Cast Lower Shelf E Couplers with compatible shank (1968-current). Original Sergent Style. | $20.00 | In Stock | |
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RC87K | 6 Easy-to-Assemble Die Cast Sharon Couplers with compatible shank (up to about 1940). Original Sergent Style. Note that we do not recommend assembly of these kits without the AFRC assembly fixture listed below. See instructions here. | $10.00 | In Stock | |
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ENC87KD | 6 Easy-to-Assemble Die Cast AAR Type E Coupler with narrow shank (no boxes included) See Accurail Site to order boxes from them. (Accurail Item #1031 or #1081.) Original Sergent Style. | $20.00 | In Stock | |
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SBEN87KD | 6 Easy-to-Assemble Die Cast Lower Shelf E Couplers with narrow shank (no boxes included) See Accurail Site to order boxes from them. (Accurail Item #1031 or #1081.) Original Sergent Style. | $20.00 | In Stock | |
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RNC87K | 6 Easy-to-Assemble Die Cast Sharon Couplers with narrow shank (up to about 1940). No draft gear box or mounting screws included. Suitable for both HO and HOn3. Note that we do not recommend assembly of these kits without the AFRN assembly fixture listed below. Original Sergent Style. See instructions here. | $10.00 | In Stock | |
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RNB87K | 6 Easy-to-Assemble Die Cast Sharon Couplers with narrow shank (up to about 1940). No draft gear box or mounting screws included. Slightly shorter shank than RN87. Suitable for Blackstone Models and other HOn3 equipment. Note that we do not recommend assembly of these kits without the AFRNB assembly fixture listed below. Original Sergent Style. See instructions here. | $10.00 | In Stock |
Hybrid Couplers
| Picture | Part # | Description | Price | Status | Buy Now |
|---|---|---|---|---|---|
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EC87P100KH | 6 Easy-to-Assemble Type E Couplers with +0.100" extended compatible shank. Shank is investment cast. Knuckle and bottom cover are die cast. Original Sergent Style. | $20.00 | In Stock | |
| EC87P130KH | 6 Easy-to-Assemble Type E Couplers with +0.130" extended compatible shank. Shank is investment cast. Knuckle and bottom cover are die cast. Original Sergent Style. | $20.00 | In Stock | ||
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EC87M040KH | 6 Easy-to-Assemble Type E Couplers with -0.040" shortened compatible shank. Shank is investment cast. Knuckle and bottom cover are die cast. Original Sergent Style. | $20.00 | In Stock | |
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SBEC87P100KH | 6 Easy-to-Assemble Type Lower Shelf E Couplers with +0.100" extended compatible shank. Shank is investment cast. Knuckle and bottom cover are die cast. Original Sergent Style. | $20.00 | In Stock | |
| SBEC87P130KH | 6 Easy-to-Assemble Type Lower Shelf E Couplers with +0.130" extended compatible shank. Shank is investment cast. Knuckle and bottom cover are die cast. Original Sergent Style. | $20.00 | In Stock | ||
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SBEC87M040KH | 6 Easy-to-Assemble Type Lower Shelf E Couplers with -0.040" shortened compatible shank. Shank is investment cast. Knuckle and bottom cover are die cast. Original Sergent Style. | $20.00 | In Stock | |
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SEC87KH | 6 Easy-to-Assemble Double Shelf SE Couplers with compatible shank (1975-current). Shank is investment cast. Knuckle and bottom cover are die cast. Original Sergent Style. | $20.00 | In Stock | |
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SEN87KH | 6 Easy-to-Assemble Double Shelf Type SE Couplers with narrow shank (no boxes included) See Accurail Site to order boxes from them. (Accurail Item #1031 or #1081.) Shank is investment cast. Knuckle and bottom cover are die cast. Original Sergent Style. | $20.00 | In Stock |
Investment Cast Couplers
| Picture | Part # | Description | Price | Status | Buy Now |
|---|---|---|---|---|---|
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EC87K | 6 Easy-to-Assemble AAR Type E Couplers with compatible shank (If you're new to our couplers and wonder what you need to try first -- this is it!) | $15.00 | In Stock | |
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EC87P100K | 6 Easy-to-Assemble Type E Couplers with +0.100" extended compatible shank. | $15.00 | In Stock | |
| EC87P130K | 6 Easy-to-Assemble Type E Couplers with +0.130" extended compatible shank. | $15.00 | In Stock | ||
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EC87M040K | 6 Easy-to-Assemble Type E Couplers with -0.040" shortened compatible shank. | $15.00 | In Stock | |
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SBEC87K | 6 Easy-to-Assemble Lower Shelf E Couplers with compatible shank (1968-current). | $15.00 | In Stock | |
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SBEC87P100K | 6 Easy-to-Assemble Type Lower Shelf E Couplers with +0.100" extended compatible shank. | $15.00 | In Stock | |
| SBEC87P130K | 6 Easy-to-Assemble Type Lower Shelf E Couplers with +0.130" extended compatible shank. | $15.00 | In Stock | ||
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SBEC87M040K | 6 Easy-to-Assemble Type Lower Shelf E Couplers with -0.040" shortened compatible shank. | $15.00 | In Stock | |
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SEC87K | 6 Easy-to-Assemble Double Shelf SE Couplers with compatible shank (1975-current). | $15.00 | In Stock | |
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FC87K | 6 Easy-to-Assemble Type F Couplers with compatible shank (1954-current). | $15.00 | Out of Stock |
Next Run Spring 2024 |
| FC87P100K | 6 Easy-to-Assemble Type F Couplers with long compatible shank (1954-current). | $15.00 | Out of Stock |
Next Run Spring 2024 |
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| FC87M040K | 6 Easy-to-Assemble Type F Couplers with short compatible shank (1954-current). | $15.00 | Out of Stock |
Next Run Spring 2024 |
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AMTC87K | 6 Easy-to-Assemble "Spear" Couplers with compatible shank (2023-current). Prototypical for SC44s and ALCs. | $15.00 | In Stock | |
| AMTC87P100K | 6 Easy-to-Assemble "Spear" Couplers with long compatible shank (2023-current). Prototypical for SC44s and ALCs. | $15.00 | In Stock | ||
| AMTC87M040K | 6 Easy-to-Assemble "Spear" Couplers with short compatible shank (2023-current). Prototypical for SC44s and ALCs. | $15.00 | In Stock | ||
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HC87K | 6 Easy-to-Assemble Type H Couplers with compatible shank (1940-current). | $15.00 | Out of Stock |
Next Run Spring 2024 |
| HC87P100K | 6 Easy-to-Assemble Type H Couplers with long compatible shank (1940-current). | $15.00 | Out of Stock |
Next Run Spring 2024 |
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| HC87M040K | 6 Easy-to-Assemble Type H Couplers with short compatible shank (1940-current). | $15.00 | Out of Stock |
Next Run Spring 2024 |
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ENC87K | 6 Easy-to-Assemble AAR Type E Coupler with narrow shank (no boxes included) See Accurail Site to order boxes from them. (Accurail Item #1031 or #1081.) | $15.00 | In Stock | |
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SBEN87K | 6 Easy-to-Assemble Lower Shelf E Couplers with narrow shank (no boxes included) See Accurail Site to order boxes from them. (Accurail Item #1031 or #1081.) | $15.00 | In Stock | |
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SEN87K | 6 Easy-to-Assemble Double Shelf Type SE Couplers with narrow shank (no boxes included) See Accurail Site to order boxes from them. (Accurail Item #1031 or #1081.) | $15.00 | In Stock |
Our couplers do not come pre blackened. This is so we can accommodate customers that may not want to handle parts that have had any chemical treatment. If you would like your couplers chemically blackened before they are sent to you please specify so in your order. Each pack costs $1.00 to blacken.
Please make sure you adjust the quantity in your cart to match the amount of couplers you want blackend. If this quantity does not match we will refund the BLK and dispatch your order unblackend.
| Part # | Description | Price | Status | Buy Now |
|---|---|---|---|---|
| BLK | Chemical Blackening per pack | $1.00 | In Stock |
Steam Pilot Solutions
Steam locomotive pilot couplers present an interesting challenge for modelers. Perhaps nowhere else is a coupler so prominently displayed as mounted the on the pilot of a steam locomotive. Traditional knuckle couplers mounted to the front of the locomotive never seem to look right. In the past, modelers have always had to compromise in this regard. One could install a working coupler which was necessary for realistic operation, or one could install a dummy coupler which can be made to look more realistic at the sacrifice of realistic operation. Manufacturers of model steam locomotives have produced both examples of this compromise.
To further complicate the issue, many model locomotive coupler pockets are not electrically insulated. This is particularly true for brass and diecast steam engines. Unfortunately, the coupler pocket on the tender is almost always electrically connected to the opposite polarity of the one on the pilot. This means you can never doublehead engines of this design unless the couplers themselves are created from an insulating material such as plastic.
Prototype Couplers offers a solution for this. The ES1P87K and RS1P87 kits includes a coupler with a modified shank that allows it to be pinned in the pocket(Sold Separately) just like the prototype. The pocket itself is offered in a all-metal investment cast(Pictured) which is not electrically isolated, or a 3D printed resin to satisfy to electrical isolation requirement and is very highly detailed. The pocket is screw mounted to the pilot beam by means of a 3/32" diameter post located on the back of the pocket.
| Part # | Description | Price | Status | Buy Now |
|---|---|---|---|---|
| ES1P87K | Type E Stub Shank Coupler
This kit includes parts for one stub shank coupler. A hole in the shank allows the coupler to be held in place with the included non-magnetic pin. These are hand machined from a regular EC87. No pocket is included (See below). |
$10.00 | In Stock | |
| RS1P87K | Sharon Stub Shank Coupler
This kit includes parts for one stub shank coupler. A hole in the shank allows the coupler to be held in place with the included non-magnetic pin. No pocket is included (See below). |
$6.00 | In Stock | |
| RS2P87 |
Metal Pocket for Stub Shank Coupler
This pocket has a 3/32" round mounting post that is threaded 0-80 for flexible mounting options. As this part is metal, it is not electrically insulating. |
$8.00 | In Stock | |
| RS3P87 |
Plastic Pocket for Stub Shank Coupler
This pocket has a 3/32" round mounting post with a through hole for flexible mounting options. It is electrically insulating. |
$3.00 | In Stock |
Tailor Made Couplers
| Part # | Description | Price | Status | Buy Now |
|---|---|---|---|---|
| ET1R87K | 
Kit for 1 Pair Type E couplers Tailor Made for Walthers Heavyweight passenger cars. For
installation instructions, go here.
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$20.00 | In Stock | |
| HT1R87K |
Kit for 1 Pair Type H couplers Tailor Made for Walthers Streamline passenger cars.
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$20.00 | Out of Stock | |
| ET1P87K |
Kit for 1 Type E pilot coupler Tailor Made for Broadway Limited Imports Steam Locomotives.
This coupler is designed to replace the dummy pilot on the front of some BLI Steam Locomotives. This has been tested on the HO Scale UP Big Boy, and UP FEF-3. May fit other BLI Locomotives but I have not tested them personally. |
$8.00 | In Stock | |
| ET2P87A |
1 Assembled Type E PRR Drop Coupler Tailor Made for Broadway Limited Imports Steam Locomotives.
This coupler is designed to replace the dummy pilot on the front of some BLI Steam Locomotives. This has been tested on the HO Scale Paragon4 PRR S2, and Paragon 3 PRR T1. May fit other BLI Locomotives but I have not tested them personally. This list will be updated as time goes on. These come assembled and unfinished in colour. If you want them blackened please add BLK to your order. |
$15.00 | Made to Order Lead Time: 1 Week |
Accessories
Uncoupling Tools
An MS uncoupling wand is required to operate the couplers.
This wand is simply a custom made industrial strength magnetic rod which lifts the
internal steel
ball in the coupler allowing it to open. The wand has a wire attached to one end aid
in aligning couplers in preparation for a tie as well. We don't recommend
building your own uncoupling wand from magnets you may have lying around. Customers
who have tried this have reported less than satisfactory results. A magnet that is too
strong will prevent the couplers from later locking after uncoupling. A magnet that is too
weak won't unlock the couplers reliably. These wands are constructed using the same material and techniques that Sergent Enginnering used. We have only changed how the wire attaches to the body of the wand.
| Part # | Description | Price | Status | Buy Now |
|---|---|---|---|---|
| MS | Local Uncoupling Tool | $10.00 | In Stock |
The MWRY uncoupler is provided specically for uncoupling passenger cars that have diaphrams prototypically positioned above the couplers. The plain side of the uncoupler slips in from the side between the top of the couplers and the bottom of the diaphrams. The round end of the tool can be used to open knuckles in preparation for coupling. The predecessor to this tool was actually designed by long time Sergent Engineering customer Larry Mowery.
| Part # | Description | Price | Status | Buy Now |
|---|---|---|---|---|
| MWRY | Passenger Car Uncoupling Tool | $15.00 | In Stock |
Coupler Height Gauge
Type E couplers are pretty forgiving as far a coupler height goes. Tightlock couplers (type F and H) are not. This Prototype Couplers coupler height gauge is a go/no-go type gauge so there is no need to guess whether or not coupler height is close enough. If the knuckle slips into the groove on the gauge, you are good to go. Limits for the gauge are of course based on the 32.5" to 34.5" prototype limits. The gauge is made out of 3D Printed UV Resin and should be kept away from UV light to prevent dimention creep or warpage. The bottom of the coupler has guides on the bottom that can be used to attach directly to rail. These are designed to be tight on purpose as a semi-permanent mounting solution for a car assembly track that you can use to gauge your cars as you put couplers on them. If you wish to use the gauge on your main layout track we recommend just shifting the gauge a little to the left or right so that the rail is resting outside of the guides on the bottom of the gauge. This will still give you the proper height limits while letting you easily move the gauge around the track to test individual cars.
| Part # | Description | Price | Status | Buy Now |
|---|---|---|---|---|
| HG87 | Coupler Height Gauge | $5.00 | In Stock |
Assembly Fixtures
If you plan to assemble lots of EC87K kits, you'll want an AFC Assembly Fixture. This
fixture is used to hold
the coupler together as it is assembled. The AFC is also very handy for holding the
coupler if it becomes necessary to thin the shank of the coupler for certain
installations. Note that this fixture works for EC87, SBEC87, double shelf, and tightlock couplers, but not short/long shank couplers.
A separate fixture is offered for the RC87K Sharon coupler kit. The AFRC fixture fits only the RC87 style coupler.
The AFN fixture is very useful when assembling EN87K kits.
For the Sharon coupler kits, an assembly fixture is not really an option, but a requirement. The RN87K and RNC87K share the same fixture. The RNB87 requires a different fixture because of its shorter shank.
You'll probably want a couple of extra ball and spring packets, too. Even though Prototype Couplers will gladly replace these small parts at no charge if they happen to get lost during assembly, you might want them more quickly than we can send replacements. These are cheap and nice to have on hand. Each pack comes with 12 balls and springs.
| Part # | Description | Price | Status | Buy Now |
|---|---|---|---|---|
| AFC | Resin EC87K Assembly Fixture | $5.00 | In Stock | |
| AFM040C | Resin EC87M040K Assembly Fixture | $5.00 | In Stock | |
| AFP100C | Resin EC87P100K Assembly Fixture | $5.00 | In Stock | |
| AFP130C | Resin EC87P130K Assembly Fixture | $5.00 | In Stock | |
| AFRC | Resin RC87K Sharon Assembly Fixture | $5.00 | In Stock | |
| AFN | Resin EN87K Assembly Fixture | $5.00 | In Stock | |
| AFRN | Resin RN87K and RNC87K Assembly Fixture | $5.00 | In Stock | |
| AFRNB | Resin RNB87K Assembly Fixture | $5.00 | In Stock | |
| AFRS | Resin RS1P87K Assembly Fixture | $5.00 | In Stock | |
| BP87 | Spare Ball Bearing and Spring Pack for EC87/EN87 | $2.50 | In Stock | |
| BPR87 | Spare Ball Bearing and Spring Pack for Sharon Couplers (same balls, much lighter springs) | $2.50 | In Stock |
Detail Parts
Couplers that have the cut lever attached on top are referred to
as "top operating" Couplers that have the cut lever attached at the bottom
are referred to as "bottom operating". The type E coupler
modeled by the EC87 was always available as a bottom operating coupler,
even though the top operating version seems to have been preferred initially.
Prototype Couplers offers items to assist the modeler in adding these special
details.
The BCL87 contains 10 etched brass cut lever linkages. These linkages fit into slots on the bottom of the coupler as shown in the picture. These brass etchings fit the E, SBE, and SE style couplers. The cut levers (not included) should be inserted through this linkage in a manner that allows the coupler to swing from side to side.
Type F couplers are almost always bottom operated and the linkage is mostly hidden by the coupler casting. A "J" shaped small diameter wire can be used to simulate the linkage for these couplers. The Prototype Couplers type F coupler head provides a shallow locating hole for this wire.
| Part # | Description | Price | Status | Buy Now |
|---|---|---|---|---|
| BCL87 | 10 Etched Cut Lever Linkages for Type E Couplers | $2.50 | In Stock |
Draft Gear Boxes
Prototype Couplers is pleased to release a draft gear box that allows our narrow shank HO scale couplers to be used in a N Scale setting. Concepted by long time Sergent Engineering customer John Niemeyer, and designed and made by us to allow N scale modellers to use more prototypically accurate couplers, without the time consuming work of modifying existing draft gear boxes.
| Part # | Description | Price | Status | Buy Now |
|---|---|---|---|---|
| DGB160 | 6 - N Scale Narrow Shank Draft Gear Boxes. Replacements for Micro Train Lines 1025/1029 Draft Gear Boxes. Used in conjunction with our RNB87 Couplers to allow for prototypical operations in N scale products. Couplers sold separately. | $5.00 | In Stock |
How To Order
There are two ways to order. You can either add in stock items directly to a PayPal cart and checkout online, or you can manually fill out the form below and submit it. If you decided to use the form below we will send a PayPal invoice to you when your order is ready to dispatch. The form below may be useful if for some reason the website checkout is not working for you.
After you place your order with our integrated PayPal checkout you should receive a email comfirmation from PayPal. If there are any delays with your order we will reach out to you in a separate email. You should receive another email from PayPal when your order has dispatched.
Legacy Order Form
Please fill out the form below and hit Send. This form takes a few seconds to process, please only press Send once. You will be redirected to a comfirmation page when your order is sent.
When your order is ready to dispatch, you will receive a PayPal invoice to the email specified in the order.
YOUR ORDER WILL NOT DISPATCH UNTIL INVOICE IS PAID
Important Information
The bottom of this page will always show the latest price revision date.
If you don't see a coupler style you want here, please let us know and we will try our best to accommodate your request.
All couplers are HO scale unless otherwise noted!
All couplers come unpainted!
Pricing last revised: February 12th 2024