This 1/8 in automatic vent valve is for use in commercial and residential hydronic heating applications to provide automatic air venting for hot or cold water distribution systems. It consists of a brass body construction with male NPT connection, air vent with silicone rubber seal, brass cover, polyethylene float with valve plug and automatic vent. It has a high temperature rating and is ideal for use with glycol systems or for use as an anti-vacuum device. It can also be installed to permit the separation and dispersal of air while fluid is circulating in the system. It can be disassembled for inspection and cleaning.