The invention relates to a needle safety device for a medical device, the needle safety device comprising: a base portion having a bore extending in an axial direction there through for receiving a needle and first and second opposing jaws extending from the base portion generally in the axial direction, wherein at least a portion of the second jaw is formed from a separate structural member connected to the base portion, wherein said portion of the second jaw is deflectable with respect to the first jaw in order Lo allow a needle received in the bore of the base portion to extend all the way through the needle safety device.