Billet flywheel bolt and lock key in high grade 4340 Moly steel, heat treated, with rolled threads for race applications. There is a nice radius under the bolt head, and a matching radius on the lock key. Rolled-threads are 30% stronger than threads that are cut; cut threads leave sharp edges which can lead to stress cracks. Drilled for safety wire so you can eliminate that soft locktab. Not for Verto clutch installations.
See deep 1.5” socket STL0038, you’ll need that size socket for installation.