This kit includes: Scat forged 4.25" stroke crank, Scat bushed forged rods, Keith Black premium forged full floating pistons, locks, file fit rings, rod & main bearings, FULLY BALANCED. Choice of 6.625", 6.700" or 6.800" rod length. Choice of .030 over (4.150 bore) or .040 over (4.160 bore) pistons.