Vivaspin 20 centrifugal concentrators have been developed to offer increased volume flexibility and performance. Vivaspin 20 handles up to 20 ml in swing bucket rotors and 14 ml in fixed angle rotors accepting 50 ml centrifuge tubes. Vivaspin 20 features twin vertical membranes for unparalleled filtration speed and >100-fold concentration. Volume graduation allows to monitor the concentration process and the modified dead stop pocket simplifies pipetting of the final concentrate. For higher process flexibility, Vivaspin 20 is available with unique accessories and operating methods. For one-step desalting following concentration, a diafiltration cup filled with buffer is placed on the concentrator and spun another time to achieve 98% salt removal, instead of two spins to achieve the same result with the traditional refill and re-spin procedure. When an appropriate centrifuge is unavailable, or for single sample processing, for gas pressure filtration, Vivaspin 20 can be filled with up to 15ml and then pressurised for bench top concentration. For even faster processing, gas pressure filtration can be combined with centrifugation. "Pressure-fugation" is particularly useful for difficult or viscous samples such as serum, when using a low process temperature, or generally when minimum process time is essential. High flux PES membrane High retentate recovery > 90 % Vertical twin membrane for ultra fast concentration Universal rotor compatibility Safe sample concentration due to dead-stop volume Convenient concentrate recovery by pipetting Volume graduation for easy reading/monitoring 100-fold concentration with twin vertical membranes Additional option for pressurized operation