“CMMG Receiver Extension Mk4” has been added to your cart. View cart HomeGun PartsAR Lower PartsAR Buffer SystemWilson Combat Flat Wire Chrome Silicon AR-15 (5.56 NATO) Buffer Tube SpringWilson Combat Flat Wire Chrome Silicon AR-15 (5.56 NATO) Buffer Tube Spring$16.95 Wilson Combat Flat Wire Chrome Silicon AR-15 (5.56 NATO) Buffer Tube Spring Additional information UPC 810025506926 Manufacturer Wilson Combat Manufacturer Part Number TR-FWBS37 43 in stock Wilson Combat Flat Wire Chrome Silicon AR-15 (5.56 NATO) Buffer Tube Spring quantity Buy now Add to WishlistRemove from Wishlist Add to Wishlist