solar collector 1.size:58/1800,47/1500 2.capacity:100-20000L 3.CE,ISO9001,CCC,certificates 4.for hotels,schools, offer OEM project solar collector size: 47mm,1500mm,/58mm,1800mm, tube quantity according the tank capacity,copper pipe: material purple copper,glass tube: high borosilicate 3.3, thickness: 2.0mm,insulation: rock wool, or import PU,hailstone resistance: 25mmbracket: aluminum alloy, ...