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The Sierra K Receiver Extension Kit is the proprietary mounting system for the Sierra K Buttstock. It consists of a reduced-length, mil-spec diameter, 7075 aluminum, 5-position receiver extension, a short heavy buffer (3.5 oz), extra power spring, castle nut, and quick disconnect end plate. All parts are made of mil-spec materials and finishes and proudly Made In The USA.
Specifications
- Manufacturer:
- B5 Systems
- Category:
- buffer-tube
- Platforms:
- AR-15
- Required Component:
- Yes
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