Suitable for a Bitumen roof covering, Ubbink’s OFT/1 flat roof vent/terminal can be used in soil and vent systems, and for natural (passive) or mechanical ventilation installations. The Ubbink OFT/1 range provides a large free vent area whilst have a low Pascal resistance figure. The Ubbink OFT/1 range is available in five different flange types for different roof coverings, Asphalt, Felt, EPDM, Bitumen and PVC, to allow termination through a flat roof to ducting up to 166mm. The stack cap is fixed mechanically so that it is more secure when installed in extreme weathers, however this can be removed for servicing purposes. Features & Benefits Suitable for Bitumen roof covering Easy removal for servicing purposes Product Specifications Material: Polyethylene/Aluminium/Bitumen Weight: 2.46kg Diameter: 166mm Height Above Roof: 300mm Flange Diameter: 490mm Depth Below Roof: 350mm Free Vent Area: 20000mm2 Pressure/Airflow Resistance: 1.0Pa