5.75" (146mm) Helios Solar Glass Filter. Fits Optical Tube Diameter 5 3/8" (137mm) to 5 5/8" (143mm)

this is my neighbor's hot water system one year ago but now I added this concave mirrors which radical increase the system heat production and water heating temperature this is it once the system had six solar heaters which are connected by these houses to this tank 450 litres of hot water what the circulation between the tank and the solar heaters takes place without a pump due to the phenomenon of gravitational circulation of water however once I decided to reduce the number of the heaters by three times what two remaining heaters will produce the same amount of heat if I add the concave mirrors therefore now this system needs only two heaters and here is his part of solar radiation which increases the heat production and water heating temperature let's look at the temperature of the black surface of the circuit or which receives solarization both from Zamir and directly from the Sun