To remind customers to change their furnace filters, the filter change clock allows you to set the number of days (one to 90) and mount in any location. The clock mounts with a magnet on the equipment or any metal surface, stands on a desk, or wall mounts next to the thermostat. When filter-change-day arrives, a bright red light flashes. The compact unit measures 2- by 2-in. Contractors can use it as a giveaway on service calls to promote their business, or to resell to customers, the company says.

Video-Aire International, Inc., 2561 Gravel Drive, Fort Worth, TX 76118; 888-494-1711 or 817-589-7873; 817-595-0240 (fax); (website).