The IBM 3505 is a reader for 80-column punched cards. It can read cards punched in EBCDIC or column binary at up to 1200 cards per minute (CPM). The IBM 3525 is a multi-function punched card device, capable of reading, punching, and printing on punched cards. The 3505 contains an integrated control unit that attaches to a System/370 byte multiplexer, selector, or block multiplexer channel. An optional feature of the 3505 allows the control unit to also control a 3525, although the two are separately-addressed devices.