Amber polypropylene tubes significantly reduce light penetration through the tubes. They are ideal for the storage of light sensitive materials or for applications involving light sensitive reactions. These 50 ml conical centrifuge tubes are graduated and have large labeling areas. In supported rotors, the 50 ml tubes are rated up to 7,000 x g. In non-supported rotors, they are rated up to 3200 x g. Sterile.