This Thermolyne Cimarec 2 Magnetic Stirrer S46725 has been tested and is guaranteed to be functional. Stirrers shows signs of use/age. PLEASE NOTE: The speed adjustment dial is functional but only in the higher RPM range. When turned up to this higher range, the stirrer preforms without issue. It is only when the dial is turned below a certain threshold that stirrer turns off. This issue is present in all three of the stirrers and is reflected in list price. We urge customers to view all photos as they show overall condition, included accessories and functionality. Please feel free to contact us with any questions.