True Union ball valves (TUBVs) are constructed of Georg Fischer PVC or CPVC (other materials available upon request) with threaded or socket connections (valves up to 2 in. come with both socket and threaded ends). Each valve has an option of EPDM or Viton seals. TUBVs with vented balls for bleach service are available in PVC, with EPDM or Viton seals.