The butterfly wing blood drawing needle is a device with a smaller needle and two plastic flaps on either side, giving the appearance of wings. It’s used in venipuncture for blood collection or infusion of IV fluids or medications into small veins that are difficult to locate and reach, even superficial needles. This is because of its needle size, allowing access to these veins, and design for better grip and control. It comes in sizes 18 to 27, with the higher number being smaller or thinner, but most come in gauges 23 to 25. The standard butterfly needle only has a length of a ¾ of an inch.