Beckman 20mm Diameter Aluminum Tube Cap Assembly, Quantity Of One

This accessory is required for the Thickwall Polypropylene Ultracentrifuge Tube (part # 355642) and Thickwall Polycarbonate Ultracentrifuge Tube (part # 355631)Adapter for Tubes in Beckman Coulter Rotors for use in Ultracentrifuge Rotors: Type 70 Ti (part # 337922) Type 50.2 Ti (part # 337901)Caps are optional for these Thickwall tubes. In Type 70 Ti, the filling level for 355642 and 355631 is 16.5 mL. For 355640 and 355630, the filling leve is 7.5 mL. The maximum speeds for these open-top tubes without a cap are: Polycarbonate -- 45,000 RPM, Polypropylene -- 20,000 RPM. These tubes could withstand were tested at 25°C for 24 hours. Further tests have shown the polycarbonate tube can run at 50,000 RPM for four hours.