DVD Underground Fire Hydrants are made of ductile iron body, valve mechanism, and a spindle that controls the sealing.
When head of the hydrant is turned counter clockwise, the spindle moves down, sealing the valve at the flow direction. In the reverse action, fire hydrant shuts-off drip tight.
Underground Fire Hydrants are used with Surface Box and are buried in soil. As a result, hydrants are protected from accidents.