Fast Times^® adjustable pushrod kits are engineered to be installed without removing the gas tank or rocker covers. Not only will these pushrods install quickly and easily, they are an absolute necessity when installing any performance cam shaft that has a smaller base circle than a OE cam and/or when using high pressure valve springs. These 7/16" O.D. pushrods are made from .049" wall 4130 seamless Chrome-moly which can easily handle high valve seat pressure. The 24 thread per inch adjuster portion of the pushrod features 4140 high strength steel, with an induction hardened tip for sever service applications. Includes instructions. Fits Big Twin Evolution 1984/Later and Twin Cam 88" 1999/Later as listed.