Onboard Glow Plug Driver. This glow driver features your choice of quick and easy one button set point programming or automatic operation, so the plug received power at any throttle settings. The set point is stored in memory until changed. The green LED light indicates burned out plugs by flashing on the panel. The unit doesn't require a Y-Harness, just plug to receiver, throttle servo and to any 1.2V to 12V* battery. Only weighs 34g.

More info HERE.