The current principal application for the Equalizer is the AV-8 Harrier IIs of the United States Marine Corps, Italian Navy and Spanish Navy. The Harrier II carries the Equalizer system in a pair of detachable pods mounted on the fuselage underside, with the cannon in the port pod and 300 rounds of ammunition in the starboard pod, fed through a bridge at the aft ends of the pods that also contains the drive system for the gun (unlike previous Harriers which used dual cannons, with each pod containing a 30mm ADEN gun and its own ammunition supply). The complete installation, which includes a double-ended feed system that returns empty cartridges to the magazine, weighs 900 lb (410 kg) empty and 1,230 lb (560 kg) loaded. The detachable pods are located and shaped to be interchangeable with the usual ventral strakes or fences under the Harrier, both serving to help trap a cushion of high-pressure air under the aircraft to add lift while in hover mode. The strakes can easily be removed and the pods attached in their place, serving the same function while adding useful firepower.