Strippers, reamers and shoulder bolts Bolts with head, cylindrical body and stepped thread. As it is used for stripper plates, it is called a stripper bolt, as the stepped thread part has a shoulder, it is called a shoulder bolt, and as it has a highly accurate body that can be aligned with a reamer hole to be used for positioning and high load applications, it is also called a reamer bolt. It is available not only in a number of shapes (size) but also materials, hardness, surface processing, etc.