... 2.Antifreezing -40 degree 3.OEM provide Split pressurized Vacuum tube solar collector System1,Size:58/1800,47/1500 2,CE ... Copper pipe: material purple copper,Glass tube: high borosilicate 3.3, thickness: 2.0mm, Three target type.Insulation: rock wool or import ... plastic spraying; thickness: 2.0mmHeat Pipe Evacuated TubeVacuum TubeThree high vacuum tube, ALN/ALN-SS/CU absorber coating, Dia: 58mm, Length: ...