Unpressurized Solar Energy: 1.High Quality And Long Life 2.Competitive Price 3.Environment Friendly ... Steel/Stainless Steel.4.Accessorues:Electrical Heating,SafetyValve,Magnesium Bar,Temperature Sensor,Controller,Electrical Elements,etc.Features:1.Pipeline Is Made ... Copper And Conducted By Heat Transfer Medium Liquid.2.Temperature Preservation Is Equipped With Standard Electric Water Heater Setting, ...