Products Home/Dampers/Radial Dampers Product Categories Aluminium Eggcrates Ceiling Diffusers Grilles Swirls Linears Jet Diffusers Floor Diffusers Weather Louvres Plastic Grilles Supply Air and Plenums Fire Damper Dampers Zoning Accessories Radial dampers are made of galvanized steel. Size available: D150 (6″) D200 (8″) D250 (10″) D300 (12″) D350 (14″)