... Heat pipe solar collector heating System 1.SOLAR KEYMARK,SRCC,CE 2.Antifreezing -40 degree 3.OEM provide Split pressurized Heat pipe solar collector heating System1,Size ... mm, Hole spacing: 75mm, max operation pressure 6 bar, phosphor copper brazingEnd CoverNylonDust RingSilicone Rubber 110Tube holderNylon 66FrameFrameAluminum alloy with plastic ...