Important Notice: 1. Automatic ventilation of greenhouse can not be used at temperatures above 50° (122 F) 2. Make sure that your greenhouse window opens normally Specifications: Maximum height of the window opening about 45cm The temperature of complete opening about 30° (depending on adjustment and load) Maximum weight vents not more than 7kg/15lb, Opening temperature regulated 16° to 25° Note When you receive this item in summer, you need to put the black bar into the refrigerator not less than 5 minutes to make the cylinder retracted fully before you assembly this product. Color: Black and Silver Material: aluminium alloy Package Contents: 1 x Automatic Window Opener kit Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is 1-3cm.