Celso Tilt and turn windows can be opened fully like a casement window (inwards) or they can be tilted from the bottom so that the top of the window is angled into the room, giving a smaller opening for ventilation. Celso's Tilt and turn windows are exceptionally easy and comfy to use. Celso's Tilt & Turn windows are designed to enhance safety standards by internal hardware with multiple locking points. Concealed hinges are designed to provide the illusion of a Fixed windows while remaining operable and no obtrusive hardware distracting the eye, lends itself to a more modern aesthetic. The performance of a tilt and turn window is superior. Better air seals yield a tighter seal, creating an air-tight window.