Chase brand micro-hematocrit tubes are manufactured from soda lime glass, packed in plastic vials with reclosable snap-lock caps to maintain cleanliness.
- Ends may be sealed by flame or sealing clay
- They are available in borosilicate glass as a special order
- Heparinized capillary tubes are treated to prevent blood clotting
- Ammonium Heparin does not interfere with sodium identification