Falcon® 15 mL high-clarity polypropylene (PP) conical centrifuge tubes have a 12,000 RCF rating. The tubes come with polyethylene dome seal screw caps, which offer both vented and fully closed positions. The sterile tubes are packaged 50 per bag and 500 per case. RNase/DNase-free. Approximate dimensions: 17mm O.D.; 120mm length Sterilized by gamma irradiation, noncytotoxic and nonpyrogenic Dark blue printed graduations and white writing patch Polyethylene dome-seal screw cap offers positive seal over full circumference