The Eaton E-Locker's electromagnetic locking mechanism is the next generation of aftermarket differential technology. Performs as an open differential until you decide that you need more traction. Eaton ELocker is your push button solution to almost any traction problem. Designed expressly for 4-wheel drive systems to give you the ability to lock or unlock the differentials when necessary. When locked the Eaton ELocker performs as a full locker, capturing 100% of available torque and sending it equally to both ends of the axle. The ELocker is built with precision-forged gears that are designed to mesh perfectly, providing improved strength and durability over a standard cut gear. Its ease of installation, reliability and push-button activation make ELocker an absolute must for all traction and off-road performance applications. This unit fits all 30 spline standard Dana 44 high or low pinion applications that are using a 3.73 and down ratio ring and pinion. Kit includes instructions and all installation hardware.