Evacuation Valves (or Vacuum Seal-Off Valves), part of the complete line of CVI Valves, have been designed to fulfill system design requirements for a safe, reliable method of vacuum closure. These valves serve as pump-out and isolation valves, as well as safety release devices. They offer added reliability when used with vacuum vessels, vacuum insulated cryogenics storage and transport containers, and vacuum insulated transfer lines where permanent or semi-permanent vacuum is required.