Patent-pending Sway Command Tow Control Technology makes towing safer by applying the trailer brakes before sway can get out of control. Uses an accelerometer (measures lateral force) and gyroscope (measures angular velocity) to quickly and accurately differentiate between side-to-side and up-and-down movement to prevent false activation. Advanced microprocessor electronically detects trailer sway and applies the trailer brakes in pulses to suppress sway without locking up trailer brakes. Light pod mounts to front of trailer and signals to driver when system is functioning properly. System works independently of existing brake control; in case of a short or disconnect, neither Sway Command or brake control will be affected. Works with weight distribution hitches with sway control systems. Rigorously tested in sway-inducing towing conditions, including emergency maneuvers. 12-volt. What Causes Sway? Emergency Maneuvers Hilly, Uneven Highways | Lippert Sway Command Tow Control