The inner wall contains the ultrafine grained sodium fluoride and anticoagulant ingredients that are spray-dried.

The inner wall is evenly sprayed with a coagulant containing a silicon component and the release gel is located at the bottom of the tube. Collect venous blood samples, mix well and let stand for 15-30 minutes, centrifuged for 8-10 minutes.

Without any additives, until the blood is fully coagulated and centrifuged, serum samples can be separated.