Installing manifolds can be frustrating when the bolt holes don’t match up. You can spend hours trying to mount a warped manifold without the proper tool. The Powerbuilt Exhaust Manifold Spreader spreads warped manifolds on GM small-block V8s and V6s so that bolt holes line up correctly. This tough steel spreader uses a 3/4-inch hex wrench which can be used in pairs. Meets or exceeds ANSI standards. Lifetime warranty.