The IBM Retail POS Keyboard was one of five Model M-designated POS input devices introduced with the IBM 4694 POS Terminal in June 1993 and is a 50-key functional keypad. The Model M7 family was the standard keypad for IBM's POS terminals from thereafter. The difference between M7-1 and M7 is that M7-1 lacks a magnetic stripe reader. In its default layout, 49 of the 50 keys are individual, and the middle bank has a numeric keypad made up of single-unit keys with the zero key taking up two key positions (hence 49). The single key on its own serves as a dedicated Ctrl key. The other slightly larger keys are designed to be programmable and thus have transparent keytops.