VWR Corks. The top of each dispensing cork is completely free of air moisture and chemical additives ensuring effective performance every time. A patented spring-loaded ball eliminates breakage and enables smooth pouring. One end of the cork is left unfinished for an added finishing touch while the other end is finished and ready to accept a branded label letting you easily and quickly create custom inks or gravimetric weights. The finely-ground cork top minimizes breakage and recovery while the spout funnel makes it easy to insert the spout into bottles and jars. Constructed from medical-grade and FDA-grade materials these dispensing products meet all USP EU and FDA Directive requirements. Each caliber listed below is certified to correspond to a standard spherical flask. Specifications for VWR Corks 51524 : Number: 15 DiameterTop mm: 33 DiameterBottom mm: 27 Lengthmm: 31 (Please note that the description and stock photo may not correspond to the specific model listed above) We offer only genuine Manton Cork products authorized for sale in the U.S. and other markets so you can be sure that you are buying authentic Laboratory Consumables with a full manufacturer's warranty in addition to our own 100percent Satisfaction Guarantee. We are your premier online distributor for VWR Laboratory Consumables. 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 Corks 51524/ 23420-366 we carry a full complement of Laboratory Consumables as well as other product offerings from Manton Cork. We also carry a full line of VWR accessories to help meet your laboratory and scientific needs. For a complete selection of VWR Laboratory Consumables please visit our Manton Cork page. For more brand name Laboratory Consumables please visit our Laboratory Consumables store section. To see our complete line of lab medical industrial and scientific products please see our science and lab equipment online catalog. VWR Corks 51524