Microhaematocrit Tubes. These capillary tubes are designed for both safe blood collection as well as an accurate microhaematocrit determination. Precision molded, they provide excellent sample retention during centrifugation. Tubes fill rapidly without affecting specimen integrity. Standard 75mm microhaematocrit tubes packaged in a protective snap cap vial. Available in Red Tip Heparinized Tubes or Blue Tip Plain Tubes. 100 tubes per vial.