The Exotek DR10 Aluminum Differential Gear Case is a heavy duty machined 7075 alloy differential case for the DR10 and is great option for high powered drag racing applications. Precision machining offers a perfect roundness that creates a free spinning transmission. This is much stronger than the stock plastic diff gear but not indestructible so it is important to use black or white grease on the gears and reapply frequently to prolong its life. Package includes one diff case and one diff cover.