Corning® 50 mL clear polypropylene (PP) self-standing centrifuge tubes come with the advanced polyethylene CentriStar™ caps and are bulk packed 25 per bulk bag. The CentriStar™ cap has an easy-on/easy-off flat top and offers advanced ergonomics with its wider knurls and roll-over edge design for easier gripping. This leak-proof design comes with a revolutionary plug feature that virtually eliminated all seepage when used under recommended conditions. Maximum RCF is 3,000 xg Temperature range from -80°C to 120°C 5 year shelf life Leak proof design Easy-on/easy-off cap Clear accurate graduations Large white marking spots RNase-/DNase-free Heavy-metal-free color concentrate Nonpyrogenic Sterile