This permits installation of tapered bearing races and seals without damage to the component or housing. The tapered side of the driver is used to install races. It"s simple; just invert the driver to the flat side to install seals. This great set includes the following: driver handle with bolt, plus these tool sizes: 1.565", 1.750", 1.965", 2.325", 2.470", 2.555", 2.830", 2.995" and 3.180".