The KAK Shockwave Blade Receiver Extension Pistol Brace Buffer Tube features 12 length adjustment settings and an anti-rotation and anti-thrust design which stays put without sliding forward or spinning. The tube is flush with the rear of the Shockwave Blade when fully collapsed. When fully adjusted out, the assembly is very rigid. A strong castle nut design accepts all mil-spec endplates and any aftermarket endplate. Accepts all carbine buffer systems.