shear nut/ security nut

Permafix shear nuts and shear bolts are are designed to provide a permanent one way fixing. They are installed using standard tooling (e.g. spanner, socket set, etc.). When the nut or bolt is fully tightened, the hexagonal drive head is designed to shear offas additional torque is applied, leaving the shear bolt or the threaded conical lower collar of the shear nut in position on the standard bolt or stud thread, thus making these products permanent fixings. When the drive flange of the shear nut shears off, only the threaded conical fixing remains in place. This offers a high security fixing as the cone shaped nut is designed to prevent any purchase point thus making removal very difficult.