IBM IL1210 - page 24

The projector is equipped with a self-locking, quick-release elevator foot and
button. To raise the projector:
1. Press and hold the elevator button 1(see the following illustration).
2. Raise the projector to the height that you want, then release the button to
lock the elevator foot 2 into position.
14 iL1210 IBM MicroPortable Projector: User’s Guide