Camplux 3.54'' (90mm) Rain Cap, Stainless Steel Rain Cap for Tankless Water Heater, Rain-Proof & Windproof Cap for Gas Water Heater, Perfect for Outdoor InstallationCamplux stainless steel rain cap. Compatible with all venting diameter at 3. 54 inch (90mm) tankless water heater. Prevents rain water, leaves or other objects from running down into your tankless gas water heater. Rain proof and wind proof can improve your tankless water heater performance in a high wind and raining day. Stainless steel venting for vertical terminations only. Specifications: 1 Year warranty Model: RC354 Diameter: 3. 54'' 90mm