The B5 Systems Sierra K Extension Kit, Fits AR15, Black is a stock / buffer component.
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.
Specifications
- Brand: B5 Systems
- Color: Black
- Manufacturer Part #: SRK-1660
- UPC: 814927024793
