UltraCruz® Centrifuge Tube Rack is designed specifically for use with UltraCruz branded 15 ml and 50 ml conical centrifuge tubes. The rack can hold up to 18 (50 ml) centrifuge tubes and 25 (15 ml) centrifuge tubes. It is perfect for conical bottom centrifuge tubes and suitable for various laboratory applications. The environmentally friendly plastic rack is manufactured from polypropylene and is stackable, reusable, and recyclable. It keeps tubes organized and accessible at all times.