Attributes . 909 Ball Valve with Check; Full Flow Laboratory Serrated Nozzle; Lever Handle with GAS Index Button; Two 3/8" NPT Male Thread Inlet Shank Assemblies, May Be Used with Most Laboratory Gases, Dual Check Vacuum Breakers for Laboratory Faucets are Used for Noncontiguous Pressure, Health Hazard Applications and are Backsiphonage Backflow Preventers. This Series is Specially Made for Laboratory Faucets where Portable Hoses can be Attached and Prevent the Flow of Contaminated Water Back into the Potable Water Supply, These Vacuum Breakers can be Installed on New or Existing Faucets Without Plumbing Changes . Names