The model Mark 3, closed circuit complete thermosiphonic system, is available in various sizes and supports (inclined and flat roof). The tank features a big round flange for easy service and its cover is aluminum granulated with high quality plastic cover. The collector is a Sandwich type. The absorber is made of 2 sheets of thick steel (8 mm) with integrated canals, painted in special solar black colour. The range of Mark 3 model extends from the model 125/1.5 with a tank of 125 liters and one collector of 1.5 m2 and ends up to 300 liters combined with 4,4 or 5,1 m2 of collectors.