Upgraded with the Patented ToughNut. The ToughNut makes the barrel tip extremely strong and durable and significantly reduces the risk of breakage. Features an easy CDS System. Just Click (Click the button), Draw (Draw in fluid) and Squeeze (Squeeze to deliver). Comes with UV resistant poly barrel and versatile blue o-ring that is compatible with oil based vaccines. Ergonomic comfort grip metal handle and lever. Includes 3 colored knobs.