Places the thumb closer to the centerline of the bore; gives greater leverage and recoil control for shooters that use a high thumb hold. For shooters with smaller hands, the lower position is easier to reach and deactivate. Serrations on thumb pad help ensure positive thumb engagement. Mfg: Gunsite SPECS: Steel, blued or stainless steel, matte as-cast finish. Contact pad, 1.9" (2.8cm) long, .314" (8mm) wide. Installation requires gunsmith fitting.