The Terrafirma E Locker has the simplest operating system of any switchable diff lock, no compressor, complicated wiring loom or air lines. 2 wires and an illuminated dash mounted switch is all that is required. The uncomplicated switch arrangement also means the E Locker is the fastest switchable diff lock to install, no cutting or welding is required. A simple drilled hole for the electrical cable gland is the only machining operation that is required. A competent mechanic should take no more than a few hours to completely install a Terrafirma E Locker from start to finish. No special oils are required.