Feature●?? TUBE MATERIAL: These conical centrifuge tubes are made in high purity PP Material. They are designed to have longer-length screw caps with sealing rings to prevent leakage. [15mL,50pcs/pk], [50mL,25pcs/pk].●?? EASY TO DISTINGUISH: Plastic centrifuge tubes also include a convenient white writing patch for easy marking and identification. The patches are nice for labeling. And the test clear tubes with screw caps.●?? EASY TO READ: Black graduations of plastic centrifuge tubes are accurate to ±2%, 15mL tubes take 0.5ml as an incremental unit, 50mL tubes take 2.5ml as an incremental unit So these lab centrifuge tubes are better for science experiments.●?? AUTOCLAVABLE AND FREEZABLE: Max. RCF: 9,400g for conical bottom tubes; it is autoclavable at 121℃/249.8℉ and freezable to -80℃/-112℉.●?? WIDE APPLICATIONS: Our plastic centrifuge tubes are general used in fields of biochemistry and molecular biology,such as the separation and preparation of various biological samples.Description