Bel-Art Three-Way Stopcock for &frac14; in. to  in. Tubing; 4mm Bore, PTFE (F30895-0000) Inert wetted surface contact Pressure rating: 240 KPa (35 psi) Steam autoclavable at 121 degree C (250 degree F) This polypropylene stopcock has a detachable, watertight and inert PTFE plug that contacts any fluid being dispensed The barbed fitting end accepts 6.4 to 9.5mm (1/4 to 3/8") ID tubing