·         Shut-off seal is made by lowering the PTFE shoulder into a specially formed glass seat

·         Design is based on the Mariotte principle and assures the drop rate regardless of the liquid level

·         Internal delivery scale is graduated to allow accurate resetting on successive runs

·         Constructed of glass, PTFE, and CTFE

·         634630 series is steam jacketed; hose connections on jacket allow the introduction of steam to heat funnel contents

·         Probe FKM o-ring is size 110

·         Suitable for use under moderate vacuum

·         Standard Taper 19/22 refill valve/stopper has a special bore to permit initial equilibration of the apparatus when it is used under vacuum

·         Graduated and numbered both up and down

·         Supplied with operating instructions

·         Manufactured from 33 expansion, low extractable borosilicate glass conforming to USP Type I and ASTM E438, Type I, Class A requirements