One box of a0 evacuated tubes only.
Each evacuated tube consists of two glass tubes made from extremely strong borosilicate glass. The outer tube is transparent and allows sunlight to pass through with minimal reflection. The inner tube is coated with an aluminum nitride (Al-N/Al) coating. This selective surface is excellent at absorbing solar radiation with minimal reflection losses. During the manufacturing process, the air contained in the space between the two layers of glass is pumped out, while the top of the tubes are exposed to high temperatures. This fuses the two tubes together into a single evacuated tube.
Outer Diameter: 58mm
Inner Diameter: 47mm