Nalgene^® centrifuge tubes, Oak Ridge style 3137 with sealing cap 

Strong and tough like polycarbonate but much more acid- and base-resistant. Can be used up to 50,000 x g in refrigerated and non-refrigerated centrifuges. Must be filled to at least 80% of the total capacity. With sealing cap closure option. Before autoclaving, just set closure on top of the tube without engaging the threads.

Nalgene is a registered trademark of Nalge Nunc International.