Kimax® flask, ASTM E1406, Type II, Class II, with a quick-release connector designed as a safety feature to accommodate standard 1/4 inch I.D. tubing, not included. Tubing can remain permanently attached since the opposite end is designed to be easily assembled via a positive threaded seal. Proper positioning of the connector provides greater flask stability as tubing angled downward has less tendency to tilt the flask. Flasks are designed to take 1 atmosphere of vacuum or 29" of mercury. Made with a heavier wall than a standard Erlenmeyer flask.