The gap between the unit and the floor should be sealed with cement, and no water seepage is allowed. After the unit is installed, check again and turn the turbine shaft of the turbine by hand. If the machine is flexible, the installation is finished.Specifications: Model:A2 Head fall:6-20M Power:500W Flow:0.005m³/s Material:copper+metal Voltage: AC 220V Package Included: 1x Hydro generator. International buyers please note: a. The item "500W Micro Hydro Water Turbine Generator Turgo Wheel 6-20M Head Fall Copper Core" is in sale since Monday, July 30, 2018. This item is in the category "Business, Office & Industrial\Industrial Tools\Generators". The seller is "fzeroinestore" and is located in HK. This item can be shipped worldwide.