■ Materials: Aluminum, Stainless Steel ■ Size(W×H)：Combining With Design Sizes ■ Accessories:R2 Nylon Filter Netting, R3 Aluminum Alloy Filter Netting, R9 Stainless Steel Insect Netting ■ Feature: ? Model RM has the property of water-proof and splash-proof, which is suitable for systems of the exhaust of external wall and return air of the basement generator room.