Abstract: A syringe for the collection of arterial blood, that offers near zero resistance to blood flow, eliminates arterial-venous admixing due to aspiration, prevents air trapping, and does not require a lubricant. The syringe embodies a tubular body, a plunger with valve and capillary bore for its entire length. The forward end of plunger is concaved to center at 45 degrees. The capillary bore is communicated with the chamber through said concave surface. The plunger is valved to provide for the withdrawal, and trapping of arterial blood in the chamber. The capillary bore and valve assist operation with self-aspirating analyzers. By nature of friction between the plunger and chamber wall, the device is volume selective.