White - (picture shows terracotta version) Combustion air vent for heat producing appliances. Internal baffles reduce light and draughts. Verifiable equivalent area calculation by Advantica. HETAS approved for use with solid fuel appliances. Core drilled - suitable for retrofit installations. Grilles U.V. stabilised to protect against fading. Tube: 127mm Dia. x 358mm L Grilles: 166mm L x 160mm H