Orders may take longer than usual to process due to manufacturers having issues receiving and shipping parts. If you need to know if a part is in stock, please call prior to placing your order. We are doing everything within our control to ship orders as soon as possible.
Each PROFORM(R) Grade 8 Header Bolt is permanently assembled with a pair of special washers. When the bolt is torqued to 28+ ft-lbs, the washers' super-hardened external teeth bite into and grip the bottom of the bolt head and the top surface of the header. After being self-locked in this manner, any bolt-loosening rotation is blocked by a wedge-locking action created by the washers' interfacing, matching cams. It's an uphill climb: vibration that might ordinarily loosen the bolt actually increases the wedge-locking tension, securing the bolt even more. Because this simple wedge-locking method uses tension instead of friction, contact with oil actually facilitates the wedge effect. When changing headers, PROFORM Header Bolts can be untightened with a normal wrench, lubricated, and reused. 16 Bolt Kit 3/8" X 3/4" Long 12 Bolt Kit 3/8" X 1" Long