Made of polypropylene, these 80-well micro tube racks are autoclavable, ideal for freezing, benchtop use, storage and transporting samples. One side of the rack is designed to accommodate 0.5mL microcentrifuge tubes. The reverse side holds 1.5mL to 2.0mL microcentrifuge tubes and screw cap microcentrifuge tubes. Racks are able to be securely stacked.