The utility model refers to a disposable plastic composite device for venous blood sampling. It is designed to take an accurately defined volume of venous blood by any of the two alternative methods provided by the device, with the correct ratio of blood and reagent inside the tube, followed by storage, transportation and preparation for laboratory tests.The technical result consists of two methods of blood sampling and increased compatibility with diagnostic equipment. The device allows you to accurately take a given volume of venous blood by any of two alternative methods provided by the device, with the correct ratio of blood and reagent inside the tube, followed by storage, transportation and preparation for laboratory tests.This technical result is achieved due to the fact that a disposable plastic combined device for venous blood sampling consisting of a test tube made of transparent polypropylene, a piston with a pusher having a nozzle for the adapter with a needle, a rubber sealant is claimed, characterized in that the attachment for the adapter with needle is a combined lid made of polypropylene in the form of a narrow cylindrical spout with two protrusions on the sides for a baynet connection from one side and a wide cylindrical a ribbed base on the other side, and at the base of the spout there is a harpoon type lock for fixing the rubber insert, having a recess, while inside the wide ribbed part of the lid there is a two-turn continuous thread for reliable and hermetic fixing by winding onto the external thread of the tube, and on the outside of the combined cover there is an adapter cap made of polypropylene, having ledges on the sides for baynet connection and a harpoon-type lock at the end for articulation with a combined lid of the device, the test tube having, on one side, an outer double-flute continuous thread for reliable and hermetic fixation by screwing into the base multifunctional lid, and on the other side has an opening for the passage of t
