KIMAX™ tube made with heavier walled tubing to withstand higher centrifugation speeds Autoclavable screw-thread cap with PTFE-faced rubber liner is included but not attached GPI Finish is 24-410, Replacement cap is 45066C Capacity 40mL Max RCF 3550 Tube OD 29mm, Length 140mm Case of 12 Manufactured from 33 expansion, low extractable borosilicate glass conforming to USP Type I and ASTM E438, Type I, Class A requirements