Vacuum Blood Collection tube Compound of Sodium Fluoride and Anticoagulant Tube with Grey Cap and 1 to 5mL Volumes, PET (Plastic) Compound of Sodium Fluoride and Anticoagulant Tube aims to obtain highly stable plasma for blood glucose testing.Sodium Fluoride is a kind of inhibitor of glucose degradation,it has the function of repressing glucose metabolism and degradation.Optional Anticoagulant are potassium Oxalate,EDTA and Heparin,they could prevent blood coagulation and avoid blood hemolysis.This particular compound additive realise that blood glucose specimen could be cold storage for a long time.