These heavy duty 10mL PYREX® conical centrifuge tubes are made with increased wall thickness for greater mechanical strength. In order to conform to outside diameter and overall length limitations imposed by centrifuge rotors and supports, it has been necessary to reduce the capacity of these heavy duty tubes. The10mL tube is graduated with durable white enamel upward from the tip in 0.1mL divisions. The phenolic 15-415 GPI threaded screw cap is fabricated of a resin which is specially formulated to resist the effects of temperature and steam. For replacement caps, see No. 9999.