The Roof vent will extract air whilst the vehicle is in motion. 4 x 5mm screw holes give the vent a secure fixing. 1620sqmm Free Flow Area. This product is ideal for venting any moving vehicle / compartment that requires free flowing air. Ideal for vans, trailers, horse boxes etc. Material is LURAN, external grade bondable material. Dimensions W190mm x L285mm x H40mm.