All-glass vacuum heat collecting tubeNanometer molecular engineering is applied to greatly improve the absorption function, the heat collecting ability increase 18%, the water temperature is higher; The same sunshine makes different hot water efficiency. The unique carbonic coating is more reliable than the traditional AL-N/AL coating, and its ageing persistence is better, the coating property is longer. Advanced technology: Multi-layer magnetron sputtering gradation aluminum-nitrogen/ aluminum sun selective absorption coating improve the heat collecting efficiency of high vacuum tube. Well material: Vacuum tube is made of 3.3 high boron silicon glass tube that satisfies QB/T2436-99(idt) ISO4803-1978 standard, with high transmittance, well cold and thermal shock resistance and strong optics stability. Quality Assurance: Strictly follows the national standards GB/T17049-1997 starting from raw material purchase to finished products, all the employees cooperate well and never allow any faulty products. Specification: 47-1200\47-1500\58-1500\58-1800\ 70-1700