vacuun tubes :size:47/1500,58/1800.durable, with low unit price ... 4.Delivery date:7-15 daysolar collector(10-30pcs vacuum tubes)Specifications:size: 47mm,1500mm,/58mm,1800mm, tube quantity calculate the ... hot water(L)Dia& Length of tube(mm)Qty. of tubes(pcs)Absorber Area(sqm)Loading of 20GP/40HQMXE-SCM-58 ... .004.2061/152 more details pls contact us anytime! vacuum tubes heating collector