Falcon™ 15 mL high-clarity polypropylene conical centrifuge tubes. 6000 RCF rating for polypropylene and 1800 RCF for polystyrene. Sterilized by gamma irradiation, nonpyrogenic. Approximate tube dimensions are 17 mm O.D. x 120 mm length. Dark blue printed graduations, white writing patch. Polyethylene dome-seal screw cap offers positive seal over the full circumference. Resins are selected via an intense array of U.S. Pharmacopoeia (USP) toxicity tests. Medical-style packaging better assures sterile presentation.