B5 Systems Sierra K Receiver Extension Kit SRK-1660 7075 Aluminum 5-Position Black
by B5 Systems
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The B5 Systems Sierra K Receiver Extension Kit is the proprietary mounting system designed for the Sierra K Buttstock. Built from mil-spec materials and finishes, this reduced-length kit is engineered for compact builds while maintaining durability and reliable function. It includes a 5-position receiver extension made from 7075 aluminum, along with the key buffer system and mounting components needed for installation. Proudly made in the USA.
Product Highlights
- Proprietary Sierra K mounting solution featuring a reduced-length, mil-spec diameter receiver extension
- 7075 aluminum, 5-position receiver extension for strength and adjustable fit
- Includes short heavy buffer (3.5 oz) and extra power spring for dependable cycling
- Comes complete with castle nut and quick-disconnect (QD) end plate for secure mounting and sling compatibility
- Mil-spec materials and finishes; Made in the USA
Specifications
- Manufacturer:
- B5 Systems
- Category:
- buffer-tube
- Platforms:
- AR-15
- Weight:
- 3.5 oz
- UPC:
- 8227695067258
- MPN:
- SRK-1660
- Required Component:
- Yes
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