This is an optional Bulletproof Machined 29T/9T Differential Bevel Gear Set for use on the HPI Savage Flux HP, Savage X and Savage XL. FEATURES: High carbon steel construction Precision machined gears 29T ring gear 9T bevel gear INCLUDES: 29T ring gear 9T bevel gear Gasket Thread Lock Heavy duty grease REQUIRES: Installation on differential assembly lmm 02.23.10 ir/jxs