This Teflon® lined, ultra low profile Magnetic Vacuum Breaker is a valve designed to limit a negative pressure (Vacuum) in a typical tank trailer. A permanent magnetic force controls the movement of the valve poppet to open on demand at 4” Hg or greater. This lined vacuum breaker is designed to protect against aggressive ladings that normally would chemically attack stainless steel. All wetted surfaces are lined with a 1/8” thick Teflon® liner. The valve seat seals on a Tef-O-Sil encapsulated silicone O-Ring. This O-Ring provides complete chemical resistance and a bubble-tight seal. All working parts are kept away from the airflow paths, which promotes easy cleaning and hassle-free repairs.