Eaton Detroit Locker Differential 30 Spline 1.55in Axle Shaft Diameter Rear 11.5inThe Detroit Locker is a 100% automatic locking differential that provides ultimate traction for mild to extreme vehicle applications. Its unique, bullet proof design is engineered to keep both wheels in drive mode even if one wheel is lifted off the ground. It works in forward and reverse, and features unmatched strength, 100 percent automatic locking, and maintenance free parts. Provides Maximum Amount Of Traction To Both Wheel Ends 100 pct.