타입 = Ventilated Top Cover Width HP = 21HP Also required (for vented version) : fixing screws, pack of 100, stock No. 172-079. Protective covers for box type plug-in units. Slide-in fastening Material 1.0 mm aluminium, unplated. Without Vent Slots. Screw fastening Suitable for the installation of guide rails Material: 1.2mm sheet steel, spray finished, RAL 9006. With Vent Slots