This unique separatory funnel is manufactured with a removable PTFE stem that virtually eliminates breakage normally associated with standard glass stem stopcocks. Made entirely of PTFE, the stem attaches directly to the glass stopcockwithout o-rings or other gaskets. Glassware equipped with this PTFE stem can survive repeated forceful strikes to the stem without breakage. Supplied complete with a PE or glass stopper of the listed size.
US PATENT NUMBER 5,580,528.