New Riddler Manufacturing Differential Covers feature a Lip free smooth transition design and recessed fasteners which allow for maximum clearance. Made from high grade ductile iron with a Raised fill plug for extra oil capacity providing better cooling ability for longer gear life. The covers seal surface is CNC Machined for great cover to axle seal. Dana 44 Models also feature a Recess for locker actuator connector on Jeep TJ Rubicon Axles. Stainless fasteners and Permatex Sealant included.