Technical specifications: Cut-out dimensions: 28x28 cm, external dimensions: 32x34 cm, roof thickness: 2.8–6 cm, height above roof: 9 cm, internal frame dimensions: 31x34 cm. Installation using the sandwich principle: no drilling on the roof; the inner frame is screwed directly to the outer frame. Weight: 2.1 kg. Optional Turbo Vent F kit available for motorisation.