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Questions & Answers
Does anyone know if this will fold properly on a Zpap M92? Expert Answer

This adapter will fit a ZPAP as long as the version of the ZPAP you intend to use this adapter on has a picatinny rail on the rear of the receiver.

by Kevin, Gear Expert, December 17, 2020
Will this adapter work with CZ SCORPION Expert Answer

It will not work with a stock CZ Scorpion. The rear of the receiver needs to be M1913 Picatinny to be able to use this adapter. The CZ Scorpion does not come that way from the factory.

by Armando R., Gear Expert, March 16, 2019
Customer Reviews
Helpful Positive Review
Stock adapter by Edubya, September 16, 2021
It’s great like all Sig Products (except the plastic brace that comes in MCX/MPX pistols). This gives you the ability to fold with most AR type stocks. Just twist in the stick with buffer tube, add a castle nut and set screw and you are in business.
2/2 found this helpful
Helpful Positive Review
It’s factory Sig and if excellent quality. by Kevin, Verified Owner, April 30, 2024
This is a good choice for MPX owners and any similar weapon that uses the rear picatinny stock mount. The buffer tube screws in and is held in place by a set screw. This saves the frustration of using a castle nut in this application. The set screw e...
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2/2 found this helpful
Helpful Positive Review
Go to choice by DK, April 13, 2022
This product is legit. I ordered two other types of 1913 rail stock adapters and had to return both of them due to fitment issues. This adapter fit perfectly on my BRN-180 lower and is rock solid. If you are running a railed lower and plan on using a...
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2/2 found this helpful
Helpful Positive Review
Solid construction, no complaints. Finish is good. Easy to install and use. Will be a solid addition to any and all builds. Good lockup and easy use. I would recommend this for anyone looking for an easy fold option
1/1 found this helpful
Helpful Positive Review
works perfectly on 1913 by Jason Helper, Verified Owner, December 9, 2023
Works perfectly on any 1913 rail that’s on back of any receiver. This piece allows you to you the post and stock you wish to use. Own a few of these.
1/1 found this helpful
Helpful Positive Review
Highly recommend by Albert Switzer, Verified Owner, December 12, 2023
Great for any rifle or pistol that has a 1913 rail on the back. Folds easy and is easy to deploy. Opens up your options for a stock or brace to 'anything that fits on a buffer tube" and that's nice.
1/1 found this helpful
Read All 33 Reviews
Gun Make:
SIG Sauer
Color:
Black
Gun Model:
SIG Sauer MCX, SIG Sauer MPX
Hand:
Ambidextrous
Condition:
New

Code: SD9-BSF-ADAP-ADAPTER-X-FOLD

MPN: ADAPTER-X-FOLD

UPC: 798681551163

$110.99

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Product Info for SIG SAUER Stock Adapter - 1913 Interface Folding Knuckle

The SIG SAUER Stock Adapter - 1913 Interface Folding Knuckle lets you upgrade your gun with a Sig stabilizing brace. Install these AR15 Stocks from SIG SAUER using the integral 1913 rail on the receiver. Using the genuine Stock Adapter - 1913 Interface Folding Knuckle while creating a better shooting experience. Convert your Sig now with the easy to install SIG SAUER Stock Adapter - 1913 Interface Folding Knuckle.image

Specifications for SIG SAUER Stock Adapter - 1913 Interface Folding Knuckle:

Manufacturer: SIG SAUER
Gun Make: SIG Sauer
Color: Black
Gun Model: SIG Sauer MCX, SIG Sauer MPX
Hand: Ambidextrous
Condition: New
Fabric/Material: Metal

Features of SIG SAUER Folding Stock Adapter for MPX/MCX, 1913 Interface ADAPTER-X-FOLD:

  • Designed for use with SIG SAUER MCX/MPX firearms and compatible SIG SAUER stocks.
  • Allows folding for storage and transport.
  • Attaches to 1913 rail on rear of MCX/MPX.
  • Compatible with standard size buffer tubes.

Package Contents:

  • SIG SAUER Stock Adapter - 1913 Interface Folding Knuckle

SIG SAUER Stock Adapter - 1913 Interface Folding Knuckle Orderable Models

List of Orderable Models

  • SIG SAUER Stock Adapter - 1913 Interface Folding Knuckle, SIG MCX / SIG MPX, Black, ADAPTER-X-FOLD , MPN: ADAPTER-X-FOLD , UPC: 798681551163 , Code: SD9-BSF-ADAP-ADAPTER-X-FOLD

SIG SAUER Stock Adapter - 1913 Interface Folding Knuckle Unavailable & Discontinued Models

List of Unorderable Models

  • USED, SIG SAUER Stock Adapter - 1913 Interface Folding Knuckle, SIG MCX / SIG MPX, Black, ADAPTER-X-FOLD , MPN: ADAPTER-X-FOLD-EDEMO , Code: SD9-BSF-ADAP-ADAPTER-X-FOLD-EDEMO-RE-B
  • USED, SIG SAUER Stock Adapter - 1913 Interface Folding Knuckle, SIG MCX / SIG MPX, Black, ADAPTER-X-FOLD , MPN: ADAPTER-X-FOLD-EDEMO , Code: SD9-BSF-ADAP-ADAPTER-X-FOLD-EDEMO-RE-A
  • USED, SIG SAUER Stock Adapter - 1913 Interface Folding Knuckle, SIG MCX / SIG MPX, Black, ADAPTER-X-FOLD , MPN: ADAPTER-X-FOLD-EDEMO , Code: SD9-BSF-ADAP-ADAPTER-X-FOLD-EDEMO-RE-C
  • USED SIG SAUER Stock Adapter - 1913 Interface Folding Knuckle, SIG MCX / SIG MPX, Black, ADAPTER-X-FOLD, EDEMO19, Used, Condition Fair , MPN: ADAPTER-X-FOLD-EDEMO19 , Code: SD9-BSF-ADAP-ADAPTER-X-FOLD-EDEMO19
  • USED SIG SAUER Stock Adapter - 1913 Interface Folding Knuckle, SIG MCX / SIG MPX, Black, ADAPTER-X-FOLD, EDEMO17, Used, Condition Like New , MPN: ADAPTER-X-FOLD-EDEMO17 , Code: SD9-BSF-ADAP-ADAPTER-X-FOLD-EDEMO17
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