The Zero Retention Force Arming Unit (ZRFAU) is an electro mechanical device used on military aircraft bomb racks to arm munitions as they are released from the aircraft. EDO MBM Technology Ltd are sole owners of the proprietary rights to one such unit and act as technical support and design authority for its ongoing use and installation. The units are used in U.S. Navy BRU-32, BRU-41, BRU-42, BRU-45, the US Air Force BRU-46 & BRU-47, the Royal Australian Air Force MAU-12, the European Tornado HMERU & LMERU bomb racks.