There are a variety of supercharger pulleys that you can run in your car. There are three different varieties of grooved pulleys. Those with four, six, and twelve grooves. These pulleys are available for smooth and keyed shafts. There are also pulleys with smooth drive belt surfaces, which are also available for smooth or keyed shafts. Pulleys also come in positive offset, or extending out from the supercharger snout and negative offsets, with the pulley surface extending back over the supercharger snout. All of these varieties of pulleys are available in a number of sizes, from 2.5 inches in diameter, up to over 5 inches in diameter.