Multi Reax test tube shaker - circular vibrating For your vessels contained 2 brackets included: Recording for 26 test tubes with 10 - 16 mm diameter intake for 12 test tubes with 16-32 mm diameter Use the timer to 999 minutes for an unattended. When the set time, an audible signal sounds to set the desired speed of 150 to 2,000 r / min variable on the digital display With a 3 mm vibration orbit to achieve excellent mixing results even for large samples containing solids