VWR Centrifuge Bottles with Caps Spherical-Bottom Polypropylene Bottle With Sealing Cap. The new centrifuge bottles are made of polypropylene with a spherical-bottom shape. The older polycarbonate centrifuge bottles have been discontinued. The need for a new generation of centrifuge bottles with higher centrifugal forces has resulted from manufacturing improvements and better materials. Packaging these more centrifugal bottles has resulted in better centrifugal forces on a wider variety of samples. The new polypropylene centrifuge bottles have been designed to withstand higher centrifugal forces than those previously tested. Their improved shape allows release of centrifugal force with a smooth inside bottom greatly reducing the leakage of a puncture and reducing stress cracking that can accompany a change in temperature. New centrifuge bottles are designed to handle the higher centrifugal force with a firm support surface reducing stress on the bottle body. The sealing cap has an increased octagonal opening for better contact with the sealing surface and to provide an air-tight seal. The new centrifuge bottles have a greased flange on the neck and are butted with an enlarged spout for better gasket performance. All new centrifuge bottles are tested twice before and after centrifugation to ensure their rotor shaft distortion. Specifications for VWR Centrifuge Bottles with Caps Spherical-Bottom BMP-CE-902 Polypropylene Bottle With Sealing Cap : VolumemL: 250 MaximumRCF g: 27500 Diametermm: 59 Lengthmm: 129 (Please note that the description and stock photo may not correspond to the specific model listed above) We offer only genuine Biomedical Polymers products authorized for sale in the U.S. and other markets so you can be sure that you are buying authentic Centrifuges with a full manufacturer's warranty in addition to our own 100percent Satisfaction Guarantee. We are your premier online distributor for VWR Centrifuges. 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 Centrifuge Bottles with Caps Spherical-Bottom Polypropylene Bottle With Sealing Cap BMP-CE-902/ 47735-690 we carry a full complement of Centrifuges as well as other product offerings from Biomedical Polymers. We also carry a full line of VWR accessories to help meet your laboratory and scientific needs. For a complete selection of VWR Centrifuges please visit our Biomedical Polymers page. For more brand name Centrifuges please visit our Centrifuges store section. To see our complete line of lab medical industrial and scientific products please see our science and lab equipment online catalog. VWR Centrifuge Bottles with Caps Spherical-Bottom BMP-CE-902 Polypropylene Bottle With Sealing Cap