This is the Differential Gear and Idler Gear Set from Arrma. FEATURES: Hardened steel construction Fits the Arrma Raider, Fury, ADX-10, Vortex, Granite, and Mojave INCLUDES: Diff Gear(52T), Idler Gear(28T), Cover Plate, Fiber Gasket and four Screws jml 04.17.12 jxs 11/09/11 ir/jxs