SIBATA low-actinic amber volumetric flasks meet ASTM E-288 Class A specifications. Feature machine-blown bodies and heavy-beaded, heavy-tubing necks, tooled for ground glass stoppers. The graduation line is sharp and permanent; large, white block-letters allow the labeling to be easily read.  The low-actinic amber stained glass provides protection for materials sensitive to light. All sizes are supplied with a ground glass stopper.  Calibrated "to contain"