... : 150L,200L,250L,300L,400L,500L,600L,700L,800L............solar water collector1) Reliable, efficient, twin-glass evacuated tubes2) ... design,arbitrary combination,harmonize with the building perfectly4.intelligent control and automatic operation5.work at anytime and enjoyable6. ... 4Mpa,welding pressure 4MpaDust Ring GasketSilicon Rubber Vacuum Tubetri-element tube,High boron and silicon content 3.3, ...