No meniscus to confuse readings. Guaranteed to meet accuracy requirements of ASTM Class B, E1272, “Cylinder, Graduated, Laboratory, Glass” and all requirements of ISO Standard 6706 “Plastic Laboratory Ware-Graduated Measuring Cylinders ( except sizes -2000 and -4000).” Large blue base prevents tipping. All sizes have generous pour spout. Can be chemically sterilized without affecting accuracy. Can be autoclaved, but accuracy will be affected. NOTE: Graduated cylinders are suitable for food and beverage use. PMP resin meets requirements of CFR 21, Part 177.1520. Autoclavable/Transparent/Graduated