Replacement sealing-cap assemblies are available for selected sizes. We recommend Nalgene Centrifuge Tube Sealing Cap Assemblies (Cat. No. DS3131-0020) for 30 mL tubes and Nalgene Centrifuge Tube Sealing Cap Assemblies (Cat. No. DS3131-0024) for 50 mL tubes.
The actual brim capacity of the Nalgene Oak Ridge High-Speed PPCO Centrifuge Tubes with Sealing Cap is 42 mL, but it is designed to fit a standard rotor.