Evacuated Tubes that are used for blood collection for different laboratory tests are made up of tubes in variable sizes, and color-coded tops to indicate tube contents. The majority of blood collection tubes contain an ingredient that either speeds up the blood’s clotting (clot activator) or stops blood from becoming clot-free (anticoagulant). The following list lists the most frequently utilized blood collection tubes, along with their additives, and their uses in lab: