These Polypropylene Polystyrene tubes are generally used in RIA, Coagulation & Bacteriology. The Polypropylene tubes are clear and can withstand 3000 RCF during Centrifugation while the transparent polystyrene tubes can withstand 1400 RCF. The PP tubes can accept common acid, alkalies & solvents at room temperature while the PS tubes can accept mild bases, weak acids but not organic solvents. Material: Polypropylene