... Antifreezing -40 degree 3.OEM provide Split pressurized Vacuum tube solar collector System1,Size:58/1800,47/1500 2,CE,SRCC ... date:7-20 days.Specifications:Solar energy collector:Size: 47mm,1500mm ;58mm/1800mm, tube quantity as your requirement.Copper pipe: material ... purple copper,Glass tube: high borosilicate 3.3, ...