Vise Grip Lady P/O Finger Insert – Value 5 Pack GripsOne side of the insert is an Oval cut and the other side is a Power LiftThe Power Lift helps the bowler create more revs with the 1/4″ forward pitch that aids grip.The oval side provides the perfect natural feel for a smooth consistent release.Drill bit size required: 7/85 Pack is one size and one color. No mixingLady Vise P/O Inserts are available in 8 sizes and 9 colors.Sizes 17/32 through 3/4 have O.D. of 7/8″