Replacement TFE plug and control knob for CHEM-VAC™ high vacuum valves CG-925 through CG-934. Available with a choice of Viton, Ethylene Propylene (E.P.) or Kalrez® o-rings. Plug is sold complete with control knob and TFE stem having three o-rings. PLEASE NOTE: CONTROL KNOB IS NOT SOLD SEPARATELY ON THE CG-900 SERIES VALVES. THE 0-20mm BORE SIZE VALVE IS OUR PREVIOUS STYLE CG-500 SERIES VALVE WITH COARSE THREAD.