Vintage Pyrex Lab Glassware Erlenmeyer with lower protrusion

A vintage Pyrex lab glassware. Made by Pyrex, the vintage laboratory glass beaker with protrusion was designed to hold 500 ml. The beaker is marked: Pyrex No. 4980 500 ml
U.S.A. Stopper No 7

The beaker measures 7 1/4" Tall; 4" base diameter