NEST Scientific centrifuge tubes are ISO 9001:2008 certified, CE certified and FDA registered. All products are made of medical grade materials. The centrifuge tubes are certified RNase, DNase, and pyrogen-free and suitable for cell pelleting and separation, concentrating bacteria, yeast for DNA isolation, purification, precipitation and transformation of nucleic acids, sample storage, etc. These affordable NEST 15 mL and 50 mL Conical Centrifuge Tubes can be centrifuged up to 12,000 x g. They can also be used for general inorganic and material science lab.