Long, thin stirring rods are an essential piece of laboratory equipment used to mix chemicals and liquids for reaction purposes. Stirring rods are fabricated from glass, with steel cores, or in solid plastic, and they are chemically resistant, inert, and non-abrasive. Steel core stirring rods are ideal when extra rigidity is required and have a rounded end, whereas solid plastic rods have a tapered end. Borosilicate glass stirring rods have low thermal expansion values and feature flat ends.