Conical centrifuge tubes are made of premium polypropylene for clarity and centrifugal strength. Tubes and caps may be frozen at temperatures as low as -86˚C. The maximum centrifugal force is 12,000xg for the 15ml tubes and 15,000xg for the 50 ml tubes*. Caps have a flat top surface for easy marking and labeling. Cat. No. C2605 features a ‘skirted’ bottom that allows the tube to stand upright without a separate test tube rack. *Refers to liquids with a specific gravity of 1.0, using appropriate rotors, cushions and adapters. Packaged in:"1 case/ 20 bags of 25 tubes