This 20mm white polypropylene (PP) test tube rack has molded-in handles making carrying tubes easy. Holes are keyed with molded-in numbers and letters for easy identification of tubes. When empty they can be stacked with any other racks of the same length. Superior chemical resistance. Holds forty 20mm culture tubes in a 4 x 10 array. Non-autoclavable. Material: polypropylene (PP). Tube diameter: 16-20mm. Array: 4 x 10. Size (L x W): 28.5 x 11.5cm. 1/Pack; 4/Case. Nalgene® #: 5930-0020.