Corning® Pyrex® Class A graduated cylinders are calibrated "to contain" in accordance with ASTM E-1272 and ASTM E-542. Each cylinder is individually serialized and supplied with a Corning Certificate of Identification and Capacity, traceable to NIST standards. Useful as a mixing cylinder. SIngle metric scale with graduation markings in durable white enamel. Each features a hollow-glass Pyrex® Standard Taper stopper. For replacement stoppers, see Cat.No. 1-7650 series in the Stoppers section. Nonsterile. Reusable.