Large, black, clearly printed graduations in precise increments of 0.1 mL. Frosted writing area on each tube for labeling. Compatible for use with all standard and high-capacity centrifuge rotors. 1.5-mL polypropylene tubes can be centrifuged at up to 20,000 RCF.. Quality, food-grade construction certified to be free from DNase, RNase, pyrogen, and DNA. Supplied in resealable, tamper-evident, self-standing bags.