... is clear tempered glass. 9) Generator setting: intake air from side upper direction, exhaust air from rear side direction, quadrate steel frame ... is coated steel, inside is galvanized steel, colour: optional10) Intake and exhaust air system: 2 units, in total 4×4KW centrifugal fans ... for intake air, model YDW4.5L, air capacity is 12500m3/h for each fan; 2×7.5KW centrifugal fans for exhaust air ...