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Customer Reviews
Most Recent Reviews
rear stock adapter by Gordo Perez, December 7, 2025
Fits perfectly with my mpa defender and holds the stock amazing, will be buying one again
Most Recent Reviews
Mpa 1913 attachment by the guy, Verified Owner, September 26, 2025
Good and works as advertised. I bought x2 and they bother were good no defects.
Most Recent Reviews
1913 rail adapter by yamyam, Verified Owner, September 23, 2025
This is a must have for attaching a 1913 rail to a mpa defender series pistol. It is easy to attach and easy to remove.
Most Recent Reviews
awsome addition by yamyam, Verified Owner, September 16, 2025
This 1913 rail selection threads directly into the rear of my mpa defender pistol. This is an excellent addition to the pistol and is well worth the money.
Most Recent Reviews
Fit perfectly and does what it should! by ustactical12, Verified Owner, October 3, 2024
Installed this pic rail adapter on my Defender and it works! Was able to attach my Midwest Industries folding buffer tube and brace. Screws are small but you have three attachment points.
Most Recent Reviews
Creates adaptability by JT, Verified Owner, September 22, 2024
Allows for a 1913 rear pic rail attachment to an MPA defender. You can fit a brace or a sling attachment. Works great.
Read All 9 Reviews
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Condition:
New
Color:
Black
Gun Make:
MasterPiece Arms
Gun Model:
Universal

Code: 69H-STA-MASSTERP-RSA040

MPN: RSA040

UPC: 810151871127

10% Bonus Bucks
List: $71.99Save $4.00
$67.99

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Product Info for A3 Industries Masterpiece Arms Defender - Rear Stock Adapter

Machined from 6061 T6 aluminum and anodized in low gloss black, this rear stock adapter securely mounts to the rear of your Masterpiece Arms Defender with included hardware. This stock adapter allows the use of A3 Industries's full line of modular stocks, Skelestocks, or any other stock designed for mounting to a Picatinny(1913) rail. Simple 5-minute installation.image

Specifications for A3 Industries Masterpiece Arms Defender - Rear Stock Adapter:

Manufacturer: A3 Industries
Condition: New
Color: Black
Gun Make: MasterPiece Arms
Gun Model: Universal
Attachment Type: Picatinny
Mount Type: Picatinny

Features of A3 Industries Masterpiece Arms Defender - Rear Stock Adapter

  • 3-slot MAGPUL aluminum Picatinny(1913) rail
  • No modifications to firearm needed
  • Modular design for various cross-platform use

Package Contents:

  • A3 Industries Masterpiece Arms Defender - Rear Stock Adapter

A3 Industries Masterpiece Arms Defender - Rear Stock Adapter Orderable Models

List of Orderable Models

  • A3 Industries Masterpiece Arms Defender Rear Stock Adapter, Aluminum, RSA040 , MPN: RSA040 , UPC: 810151871127 , Code: 69H-STA-MASSTERP-RSA040

A3 Industries Masterpiece Arms Defender - Rear Stock Adapter Unavailable & Discontinued Models

List of Unorderable Models

  • USED, A3 Industries Masterpiece Arms Defender Rear Stock Adapter, Aluminum, RSA040 , MPN: RSA040-EDEMO , Code: 69H-STA-MASSTERP-RSA040-EDEMO-OB-C
  • USED, A3 Industries Masterpiece Arms Defender Rear Stock Adapter, Aluminum, RSA040 , MPN: RSA040-EDEMO , Code: 69H-STA-MASSTERP-RSA040-EDEMO-RE-B
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