This palm size, portable magnetic stirrer will thoroughly incorporate each addition of reagent in a fraction of a second. No more manual swirling! Place a water sample on the mixing platform then gently drop in the Teflon®-coated stir bar. Use the power button to turn the unit on in well-lit conditions. Use the light bulb button to start the stirrer when ambient light is poor and six LEDs below the mixing platform will light up to make color changes in the test sample easy to see. Press the same pad to stop the stirring action, or the unit will turn itself off after five minutes. The SpeedStir runs on four AA alkaline batteries at 600 rpm. Samples tube, magnetic stirring bar and batteries are sold separately.