Jebao STU Stainless Steel UVC Clarifier (75-watt) Easy screw release for Bulb / Quartz Glass Maintenance Suitable for Marine and Freshwater, Dimesnsion: 37" long x 3" diameter Inlet & Outlet Adapter 0.75", 1", 1.25", 1.5" and 2" PVC Suitable for Pond sizes up to 9,000 gallons; Max flow: 4500GPH Up to 35% more UV efficiency from the electrolytically polished reflective stainless steel barrel interior over non-reflective black plastic UVC models