Dropping one could degrade the magnet's strength or the resiliency of the soft PTFE plastic. Polygon-shaped Alnico magnet encapsulated in FDA grade Teflon® PTFE is durable and inert 50mm PTFE Stir Bar Magnetic Stir Bars With Pivot Ring, PTFE For Magnetic Stirrers And Laboratory Mixing Bar Magnetic Stirrers 3-Pack Magnetic Stir Bars | 50mm With Turning the speed control up too fast can 'throw' the stir bar or might not spin it at all. Laboratory-Grade PTFE Construction: Ensures exceptional chemical resistance and durability, suitable for a wide range of laboratory applications. Hydrophobic, high corrosion resistance, and very non reactive, Easy to clean 3-Pack of Standard 50mm (1., 96 Inch) Length: Ideal for various container sizes and compatible with most magnetic stirrers. Versatile Application: Perfect for scientific research, quality control, and educational laboratories requiring reliable mixing solutions. Proper speed is critical. Depending on your stir plate's magnet strength and the container you use, it may take a few tries to find the perfect working position. Slowly increase your stir plate speed to find the stir bar's optimal performance. Smooth Design with Single Ridge: Optimizes fluid mixing efficiency and stability during stirring processes.