A bushing's a type of bearing. It's a cylindrical lining designed to reduce friction and wear inside a hole, or constrict and restrain motion of mechanical parts. Bushing types Threaded Insert One type of bushing's the "threaded insert", a hardened metal insert with a threaded fixing hole which allows one assembly to be fixed to another by means of a screw or threaded bolt. The use of threaded insert avoids the need for a separate nut and washer on the other side of the fixed material. Suc… (More on Bushing)