B5 Systems Sierra K Receiver Extension Kit | Top Pick

Specifications

Material—-7075 aluminum

WARNING: This product can expose you to chemicals including arsenic, which is known to the State ofCalifornia to cause cancer. For more information, go toWWW.P65WARNINGS.CA.GOV

Product Overview

The B5 Systems Sierra K Receiver Extension Kit is the proprietary reduced-length 5-position receiver extension and mounting system designed specifically for the Sierra K buttstock. It uses a mil-spec diameter 7075 aluminum extension and includes the correct buffer and extra power spring setup for consistent function and stock adjustability.

Key Features

• Reduced-length receiver extension made from 7075 aluminum
• Mil-spec diameter compatibility for standard component fitment
• 5-position adjustment for fine-tuning LOP and ergonomics
• Short heavy 3.5 oz buffer paired with an extra power spring
• Includes castle nut and quick disconnect end plate for installation-ready setup

Build out your Sierra K setup with the correct factory extension kit for reliable fitment and adjustment.