This North Carolina company has refined its SWG Power Venter. Now with a sleek new look, the units are available in 4-, 5-, and 6-in. sizes. The models were especially designed for use with oil systems in cold or coastal environments, according to company officials. It uses 100% negative pressure, pulling gases through the system and exhausting them outside. This will prevent the flue gases from escaping into the dwelling. It can be used with almost all oil or gas appliances and can vent several applications at once.

Field Controls, 2630 Airport Road, Kingston, NC 28504; 252/522-3031;