A bubble free, self-priming IV set for use in the administration of liquids includes a coupling assembly for attaching the delivery system to a source of liquid and includes a coupling membrane for controlling the flow of liquid and air through the coupling assembly. The system also includes a drip chamber for receiving liquid through the coupling assembly, the drip chamber having a membrane for preventing air from leaving the drip chamber. A self leveling port is disposed within a wall of the drip chamber, the port being permeable to air, but impermeable to liquid. Finally, a patient conduit is in fluid communication with the drip chamber and further comprises a flow control plug disposed at the distal end of the conduit. The flow control plug is permeable to air but impermeable to liquid. Use of this system allows a clinician to attach a source of fluid to a patient without significant intervention, while the system self primes.
