UNIVERSAL USE - Fits most automatic window openers on the market, with or without Easy Clip system. It works particularly well with most window opener models on the market - the cylinder is compatible with common systems from different manufacturers. Up to 14 kg window weight - This strong cylinder reliably lifts windows weighing up to 14 kg (30 lbs) - ideal for side and roof windows made of glass or polycarbonate. Efficient automatic ventilation - reacts to temperature fluctuations and thus regulates the climate in the greenhouse automatically - without your intervention. TOOL-FREE REPLACEMENT - Installation is quick and easy, especially when using the Easy Clip system - done in minutes. Sustainable & Powerless - Works without electricity or batteries. The gas contained inside expands in the heat and contracts in the cold - maintenance-free, reliable and environmentally friendly.