BLUE MAX conical sterile tubes are made of high-clarity polypropylene for excellent chemical reistance. Autoclavable and freezable at temperatures ranging from -196°C to 121°C. Blue printed graduations. Polystyrene racks. Tubes should not be frozen in the polystyrene racks. The 15 ml tubes are supplied with dome seal screw caps; 50 ml tubes are supplied with standard screw caps. 15 ml tubes 17 x 120 mm; 50 ml tubes 30 x 115 mm. 15 ml tubes 6000 g; 50 ml tubes 9400 g.