Standard length shank fits Williams Foolproof, Target Foolproof, and 5D only. Mfg: Brownells SPECS: 7/32"-40 thread. 3/8" or 1/2" STD Aperture Paks include three, 3/8" or 1/2" O.D. apertures: one each with .050", .093" and .125" aperture holes. 7/8" x .050" Target Aperture Pak includes three, 7/8&q
