1 1/8-7 X 4 TENSION CONTROL BOLT A325 TYPE 1 (WITH NUT AND FLAT WASHER)

A tension control bolt, also known as a TC bolt or a twist-off bolt, is a specialized type of bolt designed for controlled and precise installation in structural applications. The head of the bolt is usually domed and is not designed to be driven. The end of the shank has a spline on it which is engaged by a special power wrench which prevents the bolt from turning while the nut is tightened. When the appropriate torque is reached the spline shears off.

Tension control bolts are commonly used in industries like construction and bridge building, where consistent and accurate tensioning is essential to ensure the safety and stability of the structure.