This a dual purpose flask features the “TWISTLOR” ACE-Seal: simply push the adapter head and the flask together and turn 90°

To remove, turn 90° in either direction, or until the nylon retainers line up with flats on the flange and the flask and adapter head come apart. Fabricated from borosilicate glass.

The flange on flask has two ground-flats opposite each other that allow nylon retainers on the adapter head to pass over. An o-ring positioned in grooves on the head and flask makes a vacuum- tight seal when the head is turned 90° in either direction.