Abstract: A system for receiving a needle includes a valve that defines a fluid flow channel, and a housing having a first end, a second end, and a receiving portion. The system further includes a septum formed from a resilient material and mounted in the housing. The septum includes a head portion including a tapered opening, a sealing portion, and an expansion portion extending from the head portion opposite the tapered opening. The expansion portion includes a chamber having a closed end, at least one relief channel, and a plurality of apertures formed in the relief channel. The plurality of apertures facilitates fluid communication between the chamber and the receiving portion when the expansion portion is in an open position.