Vacuum Blood Collection Tubes (Surgitech) 4ml Gel & Clot Activator Tubes 100's are used for the collection and separation of blood samples in clinical laboratories. These tubes contain a gel and a clot activator, which helps in the efficient clotting of blood and separation of serum from the clotted blood. The 4ml capacity tubes are designed for use in various diagnostic tests that require serum samples. The gel facilitates the separation process once the blood has clotted, providing clear serum for testing. This pack contains 100 tubes, ideal for routine laboratory use and safe blood sample handling.