The body of GEMAK hydrant of one orifice has an angular configuration while the one of two orifices has a "T" configuration. The body and the cover are constructed of ductile iron GGG40 DIN 1693.

The piston is a registered patent of GEMAK (No 960100245) and it is specially designed to eliminate the disadvantages of the other types of hydrants that are found to the market. As a great advantage could be considered that the piston and its base are made from metal, so great stability and resistance is effected. The elastic flange which is assembled between them, provides the total sealing, when the hydrant is closed. The whole activator system moves axialy by two leaders blocking the sideway movements and deformations and assuring total stability, safeness and resistance during the operation.

The elastic separation diaphragm of the valve's chamber is constructed from a very flexible material in order to effect the easy movement of the piston with minimum losses. The piston's bases except of being the leader is also a flow regulator as it erases the whirlpool caused from the pump. The valve's chamber is connected with its entrance by a special little pipe from RILSAN PA 11 DIN 7434 or copper Cu F17 DIN 17671.