Ubbink's UB19 Ludlow Plus/49 vent is a streamlined hooded unit to suit:
Redland, 49
Marley, Ludlow Plus
Sandtoft, Standard
Forticrete, V2
The UB19 unit has a free vent area of 22,000mm² and is available in 3 colours.
For the UB19 vent to be converted into a terminal for soil/mechanical ventilation add a felt sleeve and adaptor, 50544180 (product listed under roofing accessories).