Larger, ball-bearing-type casters have been added to Airmaster portable air conditioners for quieter, easier maneuvering. They feature a locking device that prevents wheels from rolling or turning. The casters are made from a softer polyurethane material that was made to better adsorb bumps. The units also feature a new handle that makes it easier to move the units. A special, textured powder coat finish hides fingerprints.

Koldwave, 260 North Elm St., Westfield, MA 01085; 413/564-5520; fax 413/568-4857.