MII is a professional analog recording videocassette format developed by Panasonic in 1986 in competition with Sony's Betacam SP format. It was technically similar to Betacam SP, using metal-formulated tape loaded in the cassette, and utilizing component video recording. Panasonic manufactured mains-powered MII editing and playback decks which accepted both the large and small tapes, as well as portable recorders which used only the small cassette.