Graduated Tubes are constructed of polypropylene or polystyrene that is optically clear for easy viewing of sample. They feature easy-to-read dark blue printed graduations, large white writing patch, and easy on/off caps. These high-strength tubes are manufactured using a state-of-the-art mold design and are made of advanced polypropylene or polystyrene resins. The tube walls are engineered to perform under high-stress situations, making these tubes the workhorse of the life sciences lab. Supplied in medical-style sterile packaging, all tubes are non-pyrogenic and non-toxic. All Falcon tubes are manufactured and tested to the highest quality standards in the industry for reliable performance and dependable research outcomes, and are manufactured in ISO 9001:2000 and ISO 13485:2003 certified facilities.