This device opens and closes your greenhouse vent panels for reliable climate control even when you’re away! No electrical power is required. Fluid-filled cylinders expand in warm temperatures. You can raise or lower the temperature setting with a simple twist of the cylinder.

Steel with paraffin in the vent opener cylinder

Rated to lift up to 15 lbs.

Depending upon installation, this vent opener will open a vent 12-18"

The opening temperature can be adjusted from approx. 65° to 80° F

12" L; weighs 1/2 lb.