Ubbink's OFT range of vents comprises capped stacks for use in asphalt and built-up felt roofs. There are two flange types denoted by the suffix F or A . Type F has an integral plastic flange for installation in built up felt roofs and Type A has a separate aluminium flange and collar to withstand the higher temperature.

• OFT/2F is a 110mm diameter breather vent for built up felt roofs
• OFT/1 and OFT/4 terminals are suitable for use with soil and vent systems for both mechanical and natural (passive) ventilation installations. Terminals are available in 110mm/131mm/166mm diameters except the OFT/1F which is only available in 110mm/166mm