Open a compatible greenhouse roof vent as temperatures rise with a heat-responsive mechanical opener. Two pivoting black arms connect the fixed frame and opening sash, with a silver piston and single return spring controlling the linkage. The cylinder needs no batteries or electrical wiring. Includes one opener assembly; greenhouse frame, glazing, plants and scene props are not included.

Material

Painted iron arm frame as source listed, Metal cylinder, piston, spring, brackets and fasteners

• One black single-spring automatic greenhouse roof vent opener
• Heat-responsive cylinder provides mechanical actuation without electrical wiring or batteries
• Two pivoting black channel arms, silver piston linkage and one return spring
• Silver slotted window bracket and perforated base mounting plate
• For a compatible freely opening greenhouse roof vent; check mounting and clearance before installation
• Greenhouse frame, glazing, plants and scenery shown are excluded

Keep pivot joints clear and follow the instructions supplied with the actual unit for fitting and seasonal storage. Do not dismantle or directly heat the cylinder, force an attached vent, or lock it against the opener.