These compact, convenient 80 well racks are designed to keep your tubes neatly and efficiently organized. They are compatible with conical and self-standing microtubes and all wells have raised, molded numbers for quick identification. The bottom of each well has been recessed to improve conical tube stability without sacrificing the stability of self-standing tubes. They are made of autoclavable polypropylene and are supplied in a rainbow pack of 5 racks (B, O, R, G, Y) or a single color of your choice.