The SBPDW brings 3-position adjustability to the AR pistol. Compatible with standard bolt carrier groups and buffers, the SBPDW gives you all of the advantages of a pistol with improved control by adding a third point of contact for stabilization. FeaturesComplete Assembly3-Position Adjustable (6.75", 8.125", 9.375")Space between rods is 1.175"Depth of the tube is 6.920"Compatible with mil-spec BCG and carbine buffersComes with adjustable nylon strap for custom fit