Description:  With conical bottoms, these screw cap centrifuge tubes are made from clear, medical grade polypropylene. The translucent tubes have white printed graduations and a large writing area. All tubes are pre-sterilized by gamma radiation and packaged to ensure and guarantee the quality. They are certified to be non-pyrogenic. Both 15ml and 50ml centrifuge tubes are available with flat-top or plug-seal caps and can be purchased in either rack or bulk packing. RCF rating is > 8,400 x G for the 15ml tubes and > 9,400 x G for the 50ml tubes.