Thermatic-Vent®
$39.95
Taxes
Automatic cold frame vent
USES NO ELECTRICITY! Opens and closes by a temperature-sensitive spring mechanism. Range 40ºF to 70ºF. Install one front vent for intake and one high in the back for a warm air exit.
Size: 10" x 18" x 3.5"
Easily installs in an 8" x 16" opening.