A magnetizing system for use in selectively magnetizing a needle of a medical device is disclosed. Once magnetized, the needle can be tracked by a needle guidance system, which assists the clinician placing the needle by visualizing on a display the position and orientation of the needle after its insertion into a body of a patient. An orientation key system is included with the magnetizing system to ensure the needle is positioned correctly in the magnetizing system. This in turn ensures that the needle is properly magnetized so as to be accurately tracked by the needle guidance system. In one embodiment a first key is included with the magnetizing system and configured to cooperatively mate with a second key included with the needle of the medical device. Various types of keys are disclosed herein.
