This lead free anti-siphon hot or cold water vacuum breaker, 1/2 inch, prevents the reverse flow of polluted water from entering into the potable water supply due to backsiphonage. It consists of polished chrome plated lead free construction, chrome hood, chemical resistant silicone seat disc, and an atmospheric vent to prevent spilling. It has a full size orifice to assure pipe size capacity and maximum flow. It is ideal for low flow, non-continuous hot or cold water health hazard installations such as on laboratory equipment.