Bolt, nut, washers for crankcase bottom for Norton singles, open frame, with NO sump guard, each, ZP. 5/16" x . Norton listed a stud in some parts books but shows a bolt in repair manuals. Some machines has studs and some had bolts. If you know more details please contact us. For sumpguard and cradle frame use 3030 Original part number: 3036 - crankcase bottom bolt E3214 - nut washer x 2
