Technology Superb European hinge technology. Both the opening tension and the gap between the frame and sash are fully adjustable. Timber Sections: Sash = 40 x 58mm. Frame = 32 x 103mm. Both the sash and frame are made from robust Baltic Pine. Gasket: The frame gasket allows for easier flashing and a better watertight seal. Aesthetics: A one piece timber catch plate, fitted in the same timber and treatment as the window, makes the mechanism or motor invisible. Ventilators: Like all ROTO products, the window has two controllable ventilators that allow passive venting which reduces condensation. Opening: Weatherproof at the top with the bottom opening to a maximum of 180mm. Cleaning Position: The unique ROTO Top Hung window can be completely reversed for total ease during cleaning. No need to climb around on the roof.