The MPX PSB is an innovative, three-position adjustable pistol stabilizing brace dimensioned to fit the receiver cuts of Sig MPX and MCX. It ships as a complete assembly, ready-to-install, along with an integral M1913 adjustable housing. Included is an adjustable nylon strap. Size Elasto-Polymer Type Brace Model MPX PSB Safety 3 Series Brace Material Elasto-Polymer Dimensions 3.87" L x 2.25" W