Emmerich 6d4000s emergency lights battery 6v 4000mah emmerich 6d4000s p the emmerich 6d4000s is an emergency lights battery rated at 6v 4000mah this powerful nickel metal hydride nimh backup battery pack is ideal for escape route lighting security and emergency lighting the battery is universal and suitable for use in most brands of emergency lighting p emmerich 6d4000s emergency lights battery 6v 4000mah