Solar water heater vacuum tube what are the specifications?
According to the film system can be divided into black film, blue film and purple membraneWhat is eccentric, plum, and so on, anyway, a lot of
According to the glass layer can be divided into 2 casing and the 3 casing, according to the length can be divided into 150016001800 or even longer
According to the diameter of the pipe can be divided into 47mm and 58mm
