Sega launched Mega-CD II in 1993 as a more compact and less expensive revision of the CD-ROM expansion for Mega Drive. It retained the essential function of the original Mega-CD: adding a CD drive, internal storage and supplementary hardware to run games combining data, digital audio and video. Unlike the first model, which sat beneath the Mega Drive and used a motorised tray, Mega-CD II placed the console alongside it and used a manual top-loading lid. Its design was intended especially to accompany Mega Drive II, although it could also be used with the first model through the corresponding extension.