Wide neck Erlenmeyer (Conical) Flask with a 250mL capacity is made from high quality, heavy duty borosilicate 3.3 glass conforming to USP Type-1 and ASTM E438 Type-1, Class A requirements. Excellent chemical resistance and strength against breakage. Features easy-to-read white enamel dual graduated scale for added accuracy when filling or dispensing, a uniform wall thickness ideal for heating, and a reinforced rim to protect against accidental impacts. Conforms with ASTM Specification E1404, Type-1, Class-1 requirements for glass conical flasks. Size: 3.3" diameter x 5.7" tall. Mouth accepts a size #8 stopper.