Rion Greenhouse Automatic Window Opener

Automatically opens and closes the roof vent/window or the louver window when temperature changes. The opener has a metal cylinder containing a mineral which expands when heated. This pushes a piston that opens the vent. As the temperature cools, the mineral shrinks and a spring closes the vent and resets the piston. The opening and closing of the vent is gradual allowing just the right amount of air flow for cooling.

Automatic Window Opener Rion Automatic Roof Window Opener Fits Roof Windows/Vents for all Hobby Gardener Series HG-8, HR-12, HG-16, HG-20, HG-24 greenhouses, all Green Giant greenhouses, and all Prestige greenhouses. $79.00 Free Shipping Quantity: Rion Automatic Louver Window Opener Fits Louver Windows for all Hobby Gardener Series HG-8, HR-12, HG-16, HG-20, HG-24 greenhouses, all Green Giant greenhouses, and all Prestige greenhouses. $79.00 Free Shipping Quantity: