BACOENG DC 12V Solar Hot Water Circulation/Circulating Pump Run on Battery or Solar Panel 36W 4.2GPM High Head Hot water circulation pump, run on battery or solar panel, Lifetime 30000 hours, work continuously; operation voltage 12V. 1/2 BSP male thread pump, with NPT fittings. Max flow rate:4.2GPM Max water head: 26.23 Feet Working Power:36W Impeller with PPS material, food grade,low noise;Stronger head and chamber. Durable magnetic rotor,fine ceramic shaft. DC Port 5.5MM*2.1MM. Easily Connect to a Solar Panel or a DC-AC Adapter. IMPORTANT: 1.Not a Self Prime Pump. 2.Please Use at Least 50W Solar Panel for Direct Connection