The expansion tanks of the ultitube series are equipped with a tube made of borosilicate glass, which, in contrast to the plexiglas often used for tube expansion tanks, has a very high hardness and scratch resistance, a very low thermal expansion and excellent chemical and thermal resistance. The glass tube has an outer diameter of 65 mm and a wall thickness of 5 mm. Both ends of the glass tube are firmly connected with metal rings made of black anodized aluminum, which do not come into contact with the cooling medium. The base and lid of the ultitube series are made of resistant acetal and screwed to the glass tube. A large opening is available for filling the expansion tank after unscrewing the lid. A filter element made of a fine stainless steel wire mesh is integrated in the bottom of the container and, in addition to functioning as a particle filter, also separates air bubbles. The filter element is integrated in a molded rubber part and can, for example, be rinsed out under running water. The seal in the upper area of the glass tube is also designed as a molded rubber part for easy assembly and is therefore securely positioned when the lid is screwed on. An aqua computer d5 pwm pump is mounted directly on the bottom of the expansion tank. The performance of the pump can be set using a pwm signal, and a speedometer signal is also available to monitor the pump function. The pump's electronically commutated ball motor runs extremely quietly and has a long service life. When developing the expansion tank, care was also taken to ensure optimum flow behavior, the result being extremely quiet and smooth operation of the pump. Fastening material for mounting on a side / rear wall or a standing mounting are included in the scope of delivery. Four soft rubber decouplers are included for decoupling. Technical specifications: filling volume: approx. 470 ml connection thread: g1 / 4 operating voltage: 8 - 24 v dc power consumption: 23 w (at 12 v) pressure at 12 v: 3.7...