1This thermoelectric cooler uses high-end refrigeration module which has high power and good durability 2Cooling block has large area that can contact more water for quick cooling 3Four hollow copper pipes with refrigerant inside would deliver heat fast for higher cooling efficiency 4120W is suitable for 30L fish tanks and 180W is suitable for 40L fish tank 5It is energy saving and beneficial to the growth and reproduction of ornamental fish Features:This thermoelectric cooler uses high-end refrigeration module which has high power and good durability.Cooling block has large area that can contact more water for quick cooling.Four hollow copper pipes with refrigerant inside would deliver heat fast for higher cooling efficiency.120W is suitable for 30L fish tanks and 180W is suitable for 40L fish tank. It is energy saving and beneficial to the growth and reproduction of ornamental fish. Specifications:Power: 120W, 180W (Optional)Voltage: DC 12VCurrent: 10A(120W), 15A(180W)Water Inlet/Outlet Outer Diameter: 8mm/0.31"Size: 143*96*162mm/5.62*3.77*6.37"Package Includes:1 x Thermoelectric Cooler