Multi-Sample Needle, 21G (Blood Collection)

Multi-Sample Needle, 21G , also known as vacuum blood collection needles or vacutainer needles, are medical devices used to collect a sample of blood from a vein. They are designed to be used in conjunction with a vacutainer, a vacuum-sealed tube system that stabilizes the blood and prevents coagulation. The needle is inserted into a vein and the vacuum in the vacutainer tube draws the blood into the tube. Once the desired amount of blood is collected, the needle is removed and the vacutainer is sealed, ready for transportation to the laboratory for analysis.