The B5 Systems B5 SRK-1660 SRK Extension Kit BLK is a testament to superior engineering and design. Crafted with a reduced-length, mil-spec diameter, 7075 aluminum, this 5-position receiver extension kit includes a short heavy buffer, extra power spring, castle nut, and quick disconnect end plate, ensuring ease of use and functional benefits for firearm enthusiasts.

Ideal for range time and training, this extension kit enhances your firearm's performance with its proprietary mounting system for the Sierra K Buttstock. B5 Systems is renowned for its innovation and quality in firearm accessories.

Key Features:
- Manufacturer: B5 Systems
- Model: SRK-1660
- Product Type: Extension Kit
- Mounting System: Proprietary
- Weight: 0.78 lbs
- Length: 10.55"
- Material: 7075 Aluminum
- Unique Features: Reduced-length, mil-spec diameter, 5-position receiver extension
- What's In The Box: Receiver extension, buffer, spring, castle nut, quick disconnect end plate