Manufactures AOV rooflights in 1.0m² and 1.5m² aerodynamic free area configurations for stairwells, lobbies and protected escape routes, with insulated upstands fabricated in house at Sidcup. The units are CE and UKCA marked as natural smoke and heat exhaust ventilators to BS EN 12101-2, aimed at flat-roof residential and commercial smoke shafts.