Kimble 45212 KIMAX Glass Round Bottom Centrifuge Tubes with Screw Caps are useful in separating neutralized sediment for culturing from specimens of sputum. Will be found useful also for other clinical work and in many microbiological applications. Made with a heavy wall to withstand higher speeds in centrifuging. Marking spot is sandblasted. Autoclavable black phenolic caps with PTFE-faced rubber liners are supplied unattached. Replacement cap is 45066C-24.