Ideal for virology, immunology, serology and hematology applications. Two plate retaining springs on platform firmly hold one to Two 96-well titer plates.Non-slip rubber platform mat increases sample visibility. Vortexing motion thoroughly mixes every well evenly. Solid-state speed control provides accurate, continuous regulation of shaking speeds from 100-2800 rpm with a 3 mm maxmium orbit. Unit shuts off automatically at end of time cycle. Heavy duty construction ensure a long life, and combined with the rubber feet keeps the unit steable and prevents "walking"