This is a Protek 48P Light Weight Aluminum Pinion Gear. These are light-weight, hard anodized, CNC machined aluminum off road pinion gears that allow your motor to spool up quicker and improve acceleration when powering out of the corners. Machined from 7075-T6 aluminum and hard anodized, these precision cut gears are durable and ideal for any 48 pitch application. Plus, the 18 tooth and larger gears have been machined on the back side to remove as much weight as possible, without sacrificing strength. These gears are available in 13 - 38 tooth variants, and the tooth count is engraved on the gear for easy identification. Each gear includes a setscrew to make installation easy. Choose the tooth count you need from the pull down menu above. Features: 48 Pitch Choose from 13 to 38 tooth sizes Hard anodized aluminum Super light weight design Etched tooth size for easy identification Less rotating mass Quicker motor spool up