The PyroceramŽ top plate of these stirrers is highly resistant to stains, corrosion and acid and is easy to clean. Stirrers provide continuously variable stirring from 60 to 1100 rpm. Microprocessor control provides superb linear control. Exclusive design monitors and regulates the stirring speed. Extra large knobs with easy to read numbers. Built-in ring stand rod mount accepts rod(not included) as noted. Includes one TeflonŽ stirring bar. For 110V, 50/60 Hz.