These precision-molded, conical and round bottom tubes are perfect for a multitude of general laboratory uses. Precision crafted of extra clear virgin polypropylene in natural and colors or clear virgin polystyrene. Tube caps are made of low density polyethylene for a secure seal and are available in a fluted plug style or dual position design that permits sample aspiration. Polypropylene tubes are autoclavable to 122°C and freezable to -80°C. Polystyrene tubes are not autoclavable but have a nominal temperature range between 90°C and -40°C. Polyethylene caps are not autoclavable, but are available pre-sterilized with many of the tube packages. Polypropylene tubes can be centrifiiged to 3000 RCF and polystyrene tubes will withstand 1500 RCF.