IMPROVACUTER• EDTA Tubes offer whole blood specimens for whole blood haematology determinations. Generally, K2 or K3 Potassic Salt of EDTA is used as an anticoagulant. The tube’s inner wall is spray-coated with an additive. IMPROVACUTER• EDTA Tubes can be used in direct sampling analyzers without actually being opened. Blood smearing should be done within 2 hours after blood collection.