KIMAX flask with a graduation ring blasted on the neck. Calibrated to contain. With a marking spot on 10 mL and larger sizes. The 1 mL and 2 mL sizes are test tube shaped. All other sizes are of a conventional flask shape. Supplied with a PTFE stopper having a color-coded handle. The 5 mL and larger sizes are designed from ASTM Specification E288, Class A unserialized requirements. Replacement stopper is 41901R.