Editing IBM Adjustable Keyboard (section)

==Design and features==
The M15 is based upon the chassis of the [[IBM_Model_M#IBM_Selectric_Touch_Keyboard_.28Model_M1.2FM2.29|Model M2]] keyboard, and uses the same lower profile style of keycaps that are incompatible with those on a standard [[Model M]] keyboard. It also uses plastic stabilizers on the large keys. Care should be taken with these as they can break easily. As with the M2, there is no metal backplate under the membrane, accounting for its flat profile and relatively light weight.

The keyboard is split into two separate halves, that can either be detached from each other, or joined together on a ball joint that allows adjustment of the angle and height at which the two halves faced away from each other. The space bar was split across the two halves. The keyboard came with a feature named "Erase-Eaze", which allowed the user to turn one of the two space bar halves into an additional backspace. There was a switch at the back of the keyboard that enabled this functionality, and the user would cycle between the left or right half acting as <code>Backspace</code> by pressing <code>Left Control</code>, <code>Left Shift</code> and <code>Left Space</code>.

The keyboard also offered a standard keyboard height adjustment feet, although there were three levels of adjustment - a short foot, a longer foot, and the possibility to further raise the slope by inserting a screw into the longer foot. An optional numeric keypad - part number 1403599, attached to a special port on the keyboard.