Simplex screw kit contains one of each of three different screws found on a variety of Simplex locks. Contains one of each of sems screw, phillips, 6-32x7/16" (11mm) R.H.M.S for clutch cover. Contains one of each of sems screw, phillips, 6-32x5/16" (8mm) R.H.M.S for combination chamber and clutch backing plate. Contains one of each of phillips screw 6-32x3/8" F.H.M.S. for back plate.