The KIMAX® Cannon-Fenske viscometer tube is designed from ASTM Specification D446. Permanently marked with an individual serial number. For use in obtaining kinematic viscosities of transparent liquids (ASTM Method of Test D445). Viscosity ranges shown are for an efflux time greater than 200 seconds, except for size 25 where minimum time should be greater than 250 seconds. Lines and legend are printed black. Tubes have not been calibrated for constant value and must be before use. Calibration against a standard liquid of known viscosity or against a second viscometer with a known constant must be made. Uncalibrated. Serialized.