Products Home/Damper/Manual Volume Control Damper 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 Manual volume control damper is made of galvanized steel. Size available:150200250300350400450