CELLTREAT® centrifuge tubes are manufactured in a class 100,000 clean room and made of high-clarity polypropylene. Graduations are printed in a bold easy-to-read black and are accurate to ± 2%. New 50mL tubes include a black printed 50 ml graduation line as well as 1, 2 and 3ml graduations molded into the conical bottom. Large white marking area provides excellent contrast for identification. The extended cap design facilitates one hand removal of caps and helps prevent contamination. Conical bottom tubes have smooth, flat surface polyethylene caps. Self-standing tubes have a plug seal polyethylene cap. Both cap styles provide an integral seal. Maximum RCF is 12,000 (g) for conical bottom tubes and 6,000 for self-standing tubes. Temperature range is -80°C to 120°C. CELLTREAT 15 and 50ml tubes are available in recyclable racks or bulk packaged in sterile re-sealable (zip closure) bags. Inner bags contain lot number information. Gamma irradiation sterilized, RNase-free, DNase-free, DNA-free, and Non-pyrogenic.