Round air diffuser is multi-storey pyramidal structure, generally installed in the ceiling of heat and cold room. Round air diffuser- Removable Core - With Butterfly Damper - Powder Coated, Standard Color RAL 9010/9016, other Colors Availble - Anodized Aluminum Availble - 5 Sizes: 150, 200, 250, 300, 350 ,400,450 (mm)