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B5 Systems
Sierra K
$135.00
$128.25
Sale Price
Available
B5 Systems Sierra K Extension Kit, Fits AR15, Black SRK-1660
Key Details
Brand
B5 Systems
Manufacturer Part Number
SRK-1660
UPC
814927024793
SKU
B5SRK-1660
Current Stock
66 available
Quantity Updated
Apr 24, 2026 8:10 PM
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Purchase Requirements
- Final availability is confirmed at checkout.
In-Store Pickup Required: All firearm purchases must be picked up at our Beverly Hills location after background check completion.
Product Description
The Sierra K Receiver Extension Kit is the proprietary mounting system for the Sierra K Buttstock. All parts are made of mil-spec materials and finishes and proudly Made In The USA.
Features
- Reduced-length 5-position Receiver Extension Constructed of 7075 Aluminum
- Includes a Short Heavy Buffer (3.5 oz), Extra Power Spring, Castle Nut and QD End Plate.
Specifications
UPC:
814927024793
Manufacturer:
B5 Systems
Manufacturer Part #:
SRK-1660
Model:
Sierra K
Model (Alt):
Extension Kit
Type:
Buffer Tube Complete Assembly
