Nalgene 3114 Oak Ridge High-Speed Teflon FEP Centrifuge Tubes with ETFE Screw Closures are ideal for high-speed centrifugation of aggressive chemicals. Excellent for chloroform and phenol extractions. Resist any acid, base or solvent. Autoclavable tubes withstand temperatures from -100°C to +150°C. For use in refrigerated and non-refrigerated centrifuges up to 50,000 x g. NALGENE sealing cap assemblies (Cat. No. DS3131) are available for all sizes. Before autoclaving, just set closure on top of the tube without engaging the threads.