Compaq Prolinea Family Maintenance & Serice Manual page 83

Feet
Four rubber feet are mounted to the underside of the base pan. No parts
have to be removed to gain access to the feet. The feet have an adhesive
surface and are shipped with a protective strip in place. If necessary,
use a small flat-bladed screwdriver to remove the old feet. Remove the
protective strip, and install the replacement feet (Figure 5-5).