B5 Systems Sierra K Receiver Extension Kit - AR-15 - 5-Position - 3.5 oz Buffer
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- Free standard shipping on orders $139+ details
- 90-day no-hassle returns policy
- Lifetime Warranty what it covers
Product description
The Compact Buffer System Built for the Sierra K Stock
Features
- Reduced-length receiver extension designed for the B5 Systems Sierra K stock
- 5-position adjustment range for compact stock configurations
- Mil-spec diameter receiver extension constructed from 7075 aluminum
- Short 3.5 oz heavy buffer matched to the reduced-length system
- Extra-power action spring included
- QD end plate provides an integrated push-button sling attachment point
- Made in the USA using mil-spec materials and finishes
The B5 Systems Sierra K Receiver Extension Kit provides the shortened buffer system required to take full advantage of the compact Sierra K stock. The complete setup pairs a reduced-length 5-position 7075 aluminum extension with the matching short buffer and extra-power spring rather than relying on standard-length carbine buffer components.
Note: This is the proprietary receiver extension system designed for the B5 Systems Sierra K stock. Sierra K stock is sold separately.
Specifications
- Brand: B5 Systems
- Model: Sierra K Extension Kit
- MPN: SRK-1660
- Fit: AR-15
- Stock Compatibility: B5 Systems Sierra K
- Receiver Extension Material: 7075 Aluminum
- Receiver Extension Diameter: Mil-Spec
- Adjustment Positions: 5
- Buffer Weight: 3.5 oz
- Color: Black
- Country of Manufacture: USA
What’s Included
- 1x Reduced-Length 5-Position Receiver Extension
- 1x 3.5 oz Short Heavy Buffer
- 1x Extra-Power Action Spring
- 1x Castle Nut
- 1x QD End Plate
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Questions & Answers
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Warranty & returns
Lifetime Warranty
B5 Systems products are backed by a lifetime warranty against defects in materials and workmanship. If a covered defect appears under normal use, B5 Systems will repair or replace the product. This warranty does not cover damage caused by misuse, modification, improper installation, or normal wear and tear.
90-day no-hassle returns
The AT3 Tactical store has a 90 day no-hassle return policy for products in good condition. You can view the full details of our return policy here.
If you encounter an issue or defect with a product after 90 days of your purchase, you can refer to the manufacturer for a warranty claim. Their policies are below.