The Endeavor functions on its ability to sense deceleration of the tow vehicle during braking. It comes with an exclusive Quik-Connect feature. An internal sensor measures the amount of deceleration and sends a proportional amount of power to the trailer brakes. The initial turn-on voltage and maximum output are adjustable to provide superior trailer brake responsiveness. The digital display will indicate the amount of power being sent to the trailer brakes and can be adjusted to display in three modes (percent of power, voltage, or current). For 2, 4 or 6 electric brakes. Lifetime warranty.