Pre-assembled with a capillary straw, pierceable cap, and a tube in various sizes and additives. Micro tube improves the quality of capillary blood samples. Hemolysis and tissue contamination are avoided by drawing the blood sample into the tube through capillary action. Clotting is prevented by having anticoagulant in both the capillary straw as well as the tube allowing the blood sample to begin mixing immediately as it is drawn into the tube.