Terumo Surflo Winged Infusion Sets have soft, flexible, interlocking wings that readily conform to the body's contour. The needles are bonded to the wings at just under a 3 degrees downward angle, for less risk of vessel damage or occlusion of the lumen. The precisely honed needle assures ease of penetration and continued access with a single insertion. Used for intravenous administration of blood or solution. Also known as 'butterfly' because of its design.