Glass Greenhouses -Stainless Steel Greenhouse Automatic Window Spring Opener Single Spring Load 7kg Highlights generic brand Stainless Steel Greenhouse Automatic Window Spring Opener Single Spring Load 7kg Description: -Automatic greenhouse window opener for solar greenhouse -Made of superior stainless steel, sturdy, maximum opening load: 7kg / 15kg -Working principle: As the temperature changes automatically, expansion and contraction thermals, the black cylinder maintains the best growing temperature and prevents your greenhouse from overheating. - Solar powered, greenhouse vents automatically open or close when temperature rises or falls. - Energy saving and eco-friendly, no electricity required. Specification: Material: Superior Stainless Steel Size: Approx. 38x10x5 cm / 14.96x3.94x1.97 inch Maximum window opening: 45 cm Maximum opening: 30 depending on adjustment and load -Single spring kit: Max. opening weight: 7 kg Adjustable open temperature range: 20-25 / 68 -77F -Dual spring kit: Maximum opening load: 15 kg Adjustable open temperature range: 15-25 / 60 - 77F Package includes: 1 Piece Greenhouse Window Opener Note: Please do not use the door opener at a temperature above 50 (122F). Please do not remove the cylinder, the opener cannot be stopped manually.