Designed in conjunction with Maxim Defense, the SBPDW Pistol Stabilizing Brace is 3-position adjustable and compatible with mil-spec bolt carrier groups and carbine buffers.Features: 3-postion adjustable Complete assembly, ready-to-install, including a proprietary buffer tube (does not include buffer/spring) Compatible with mil-spec bolt carrier groups and carbine buffers/springs QD attachment point at 6 o'clock position on housing ATF compliant, US veteran designed and proudly made in the USA Product Includes: complete assembly, adjustable nylon strapAdditional Information: The end plate and castle nut are integral to the assembly Castle nut wrenches are often steel. The SBPDW buffer tube/castle nut assembly is aluminum. Care must be taken during installation / removal to avoid damaging the nut. Space between rods is 1.175" Depth of the tube is 6.920" Not compatible with Freedom Ordnance FX-9 lowers or SIG M400/516 lowers with integral QD socketsSpecifications: FIT: Mil-spec AR-15 receivers WIDTH [MAX]: 2.25 in LENGTH: 6.75 in (collapsed), 8.125 in (mid), 9.375 (extended) in STRAP WIDTH: 1 in WEIGHT: 18.14 oz COLOR: Black