Vise Grip Oval/Nub Bowling Insert – 5 PackOne side of the insert is a full size, and the other size is a half size bigger.Drill Size 31/32″: 37/64, 19/32, 39/64, 5/8, 41/64, 21/32, 43/64, 11/16, 45/64, 23/32, 47/64, 3/4, 49/64,25/32, 51/64 and 13/16.Drill Size 1-1/32″: 53/64, 27/32, 55/64, 7/8, 57/64 and 29/32Color – Grape (Purple)”This finger insert from VISE enables me to compete at the highest level of competition in the world, the Denny’s PBA Tour. This finger insert has the best of both worlds, a very soft material fo maximum power and ‘nubs’ for a clean and consistent release. Thanks to this new finger insert, I bowled a televised 300 in the finals at the 2007 PBA Pepsi Championship!”- PBA PROFESSIONAL, Ryan Shafer