The IBM 7330 Magnetic Tape Unit was IBM's low-cost tape mass storage system through the 1960s. Part of the IBM 7 track family of tape units, it was used mostly on 1400 series computers and the IBM 7040/7044. The 7330 used 1⁄2 inch (12.7 mm) magnetic tape up to 2,400 feet (730 m) long wound on reels up to 10+1⁄2 inches (266.7 mm) diameter.