Vise Inserts IT Top Sleeve, Ball IT and Ball IT Safety MollyThis Vise IT kit includes 10 of each of the items:top sleeves for your slug – size choice (1 1/8, 1 1/4 or 1 3/8)Ball ITs for inside your thumb hole with the bowling ball.Ball IT Safety Mollys for securing the Ball IT inside your thumb hole .Vise Insert Thumb Slug It Top SleeveThis fits on 1 1/8, 1 1/4, and 1 3/8 slug sizesUse glue to adhere the top sleeve to the top of the drilled hole in the bowling ball.Vise Insert Ball ItThis is the piece that is mounted to the bowling ball.