Editing IBM 122-key terminal keyboards (section)

===Type I===
The first type of M122, the Type 1, is the earliest observed. It strongly resembles the IBM Model F 122 keyboard. From the top and sides, a Type I M122 is indistinguishable from an F122. It shares the F122’s top case, large 2-level flip-down feet, and square metal badge. The top case of the F122 is made of more brittle, painted plastic, and the M122’s case is made of the same plastic used in the Enhanced Keyboard. However, it is impossible to accurately distinguish between the two from photos. The biggest external difference is the bottom case. An F122 has a black stamped-metal bottom case with a separate plastic piece on the back, while the Type I M122 has a one-piece beige plastic bottom case. There is a blanking plate on the bottom case to which dip switches are sometimes fitted.

The top case of a Type I M122, with a little modification to the inside, can be fitted to replace the top case of an F122. Many F122 owners do this because the Type I M122’s case is made of a much more durable plastic.

The Type I M122 is generally the earliest version of M122, but some examples were produced by Lexmark in the 1990s. These Lexmark-produced examples have a unique bottom case with cutouts for drainage channels not seen on early IBM-produced Type I M122s.

Type I M122s usually have the thick, rainbow-colored backplate also found on early Enhanced Keyboards. Type I M122s also feature fixed, coiled cables with 240 degree 5-pin DIN connectors.

<gallery widths=250 heights=147>
File:IBM_1389262_31MAR94.jpg|Type I M122, P/N 1389262, made by Lexmark in 1994.
File:IBM_1389262_31MAR94_back.jpg|Back view, showing large flip-down feet
</gallery>