Serum Blood Collection Tubes No Additive Clot Activator Separation Gel Product Overview Serum Blood Collection Tubes are designed for serum sample collection and preparation in clinical laboratory testing. The range includes No Additive Tubes, Clot Activator Tubes and Separation Gel & Clot Activator Tubes , allowing laboratories to select the appropriate configuration according to testing requirements. The tubes feature an accurately controlled vacuum, silicone-treated inner