TUBE, TEST POLYSTYRENE 12X75MM5ML (1000/BG) McKesson Plastic Test Tubes Molded from premium-grade polystyrene (PS) for clarity Can withstand 1500 RPM during centrifugation. Non-graduated, translucent tubes with round bottoms Brittleness temperature: 20ºC Maximum temperature: 90ºC Not Made with Natural Rubber Latex Packaged: 1000 Per Bag