... service 4.Delivery date:7-15 daysolar collector(10-30pcs vacuum tubes)Specifications:size: 47mm,1500mm,/58mm,1800mm, tube quantity ... system completely autumatic, you can uae hot water anytime, high efficient,and no-pollution.3. installation: instal full system ... with plastic spraying; thickness: 2.0mmHeat Pipe Evacuated TubeVacuum TubeThree high vacuum tube, ALN/ALN-SS/CU absorber coating, Dia: 58mm, ...