VWR Spinbar Stir Bars Octagon Color-Coded Blue. Stirring bars without an integral pivot ring are called "spinbars". A magnet is placed in the ring and a current is generated thus stirring the mixture. After a certain point the magnet begins to lose its effectiveness; a flask rod or stirring bar that is too slow to rotate becomes stale and must be spun. A new stirring bar with a small pivot ring can be placed over the top of the corresponding grooved bar. After a certain point the bars separate and a new one takes its place. Specifications for VWR Spinbar Stir Bars Octagon Color-Coded 371095018 Blue : L x Dia. mm (in.): 50.8 x 7.9 (2 x 5/16) (Please note that the description and stock photo may not correspond to the specific model listed above) We offer only genuine Bel-Art products authorized for sale in the U.S. and other markets so you can be sure that you are buying authentic Laboratory Apparatus with a full manufacturer's warranty in addition to our own 100percent Satisfaction Guarantee. We are your premier online distributor for VWR Laboratory Apparatus. We are an authorized supplier to all federal and state government agencies as well as to research and educational institutions and can facilitate volume orders on many types of laboratory equipment lab consumables and other products to help fulfill your specific needs. We offer Free Shipping and FREE USPS shipping to APO and FPO addresses on all orders in our store over 49. Please refer to our APO/FPO Shipping and Export Restrictions for more information on export to APO/FPO addresses. In addition to the VWR Spinbar Stir Bars Octagon Color-Coded Blue 371095018/ 58949-048 we carry a full complement of Laboratory Apparatus as well as other product offerings from Bel-Art. We also carry a full line of VWR accessories to help meet your laboratory and scientific needs. For a complete selection of VWR Laboratory Apparatus please visit our Bel-Art page. For more brand name Laboratory Apparatus please visit our Laboratory Apparatus store section. To see our complete line of lab medical industrial and scientific products please see our science and lab equipment online catalog. VWR Spinbar Stir Bars Octagon Color-Coded 371095018 Blue