Unique design for superior braking creates more pressure at the brakes than in-line actuator systems. Parts have interchange ability between 6k and 8k actuators. Lock-out feature allows use with standard hydraulic brakes for backing up. No need for specific free-backing brakes. Breakaway device will set trailer brakes automaticallyy should separation from tow ball occur. 2 year limited warranty. This is a special order item, delayed in shipping time.