hybex™ Erlenmeyer Flasks, Threaded GL45 Screw Cap by Benchmark Scientific are reusable borosilicate 3.3 glass flasks with a GL45 neck and an autoclavable blue polypropylene cap and drip ring. Permanent white enamel graduations and a marking box make them easy to use for shaking, media preparation and closed storage. Sizes run from 250 mL to 2000 mL.