The Benchmark Scientific Z446KE Hermle Universal High-Capacity Refrigerated Centrifuge (No Rotor), 230V offers the highest capacity of any benchtop Hermle-Benchmark model. With air-craft grade, premium alloy construction, the 4 x 750ml swing out rotor can withstand centrifugal forces upwards of 4,000 x g with full loads of up to 28 x 50ml or 68 x 15ml tubes. Advanced microprocessor controls allow for instant rotor identification, which automatically converts the rotational speed to the relevant g-force (rcf), preventing the user from setting a speed above the capabilities of the installed rotor. In addition to retrieving saved programs, the easy to use front panel can adjust accel/decel rates, and change the end of run alarm tone. Rotor exchange is simple and requires less than one minute. An included rotor wrench can be used to loosen and install all rotors. As soon as the rotor is placed on the motor shaft, the identification process activates and the installed rotor code is displayed on the backlit LCD display.