... No. Specification Quantity(Pcs) Measurement(cm)GD030LHGGreen cap,Heparin Lithium+Gel,13×75mm,3ml120048×38×20GD050LHGGreen cap,Heparin Lithium ... +Gel,13×100mm,5ml120048×38×25 Gel & Heparin Tube is a kind of anticoagulation ... Lying at the bottom of the tube, there is some gel for separating plasma and blood cells, preventing substance from exchanging ...