Argos T7456-001 Polypropylene 0.5mL LiteSafe Graduated Microcentrifuge Tube, with Click-Fit Cap for Light Sensitive Sample Centrifugation and Autoclavable (Pack of 500) 0.5 mL centrifuge microtube with click-fit cap is made of medical grade polypropylene Can be stored at temperatures down to -100C and spun up to 15,000g's Click-fit cap provides tight seal to prevent accidental opening during centrifugation Black centrifuge Tube are completely opaque, therefore protecting even the most light sensitive compounds Autoclavable