Accessories:Main diff gear 43T-1PCPinion 13T-1PCManual number:AR310497/AR310441Product major function & usage:TRANSFER THE POWER FROM THE ENGINE TO THE CARMajor advantages of upgrading to this product:1. Made by harden steel for better strength and durability2. Higher accuracy for smooth performanceOther special notes and comments:Suitable for ARRMA , TYPHON