This heavy duty crankshaft turning nut easily installs through the harmonic balancer and into the end of the crankshaft with the included grade 8 bolt. Once that's done, your balancer is held securely, and you have turning nut that is ready to rotate whenever necessary. Product Features:Heavy-Duty ModelFits Small Block Chevy and V-6 Engine CrankshaftsMade from High-Quality SteelBlack-Oxide Finish1-inch Stud Length