A connector for coupling a medical fluid supply tube to the head of a catheter device having a circular hub having a circumferential recess defined in a side surface of the circular hub, the connector comprising: - a resilient assembly including cantilevered springs, each cantilevered spring having at least one arm, each arm having a first end, a central section, and a second end that is joined to a central support; and - a plurality of release buttons extending from the resilient assembly, each release button having a first portion including a finger contact zone and a second portion including a catch, the catch configured to releasably engage a circumferential recess defined in a side surface of the circular hub, wherein the connector is coupled to the circular hub by catches that engage the circumferential recess defined in the side surface of the circular hub such that the connector is free to rotate completely about the circular hub, wherein the connector is decoupled from the circular hub by pressing the release buttons to reversibly displace the respective catches radially to disengage from the circumferential recess, wherein the connector is coupled to the hub by positioning the connector on the hub and depressing the connector until the catches engage the circumferential recess, wherein the connector is decoupled from the hub by pressing the release buttons to reversibly displace the cantilevered springs thereby moving the respective catches radially to disengage them from the circumferential recess, characterized in that each arm of a cantilevered spring has a length measured from its connection with the release button to its connection with the central support that is from about 0.75 to about 1.25 times the length of the radius of the circular hub, and in that each arm of a cantilevered spring further defines an angle of between about 35 degrees to about 50 degrees with respect to an axis normal to the central support and wherein an upper surface of the central support is located above the transition between the first portion and second portion of the release button. - a resilient assembly including cantilevered springs, each cantilevered spring having at least one arm, each arm having a first end, a central section, and a second end that is joined to a central support; and - a plurality of release buttons extending from the resilient assembly, each release button having a first portion including a finger contact zone and a second portion including a catch, the catch configured to releasably engage a circumferential recess defined in a side surface of the circular hub, wherein the connector is coupled to the circular hub by catches that engage the circumferential recess defined in the side surface of the circular hub such that the connector is free to rotate completely about the circular hub, wherein the connector is decoupled from the circular hub by pressing the release buttons to reversibly displace the respective catches radially to disengage from the circumferential recess, wherein the connector is coupled to the hub by positioning the connector on the hub and depressing the connector until the catches engage the circumferential recess, wherein the connector is decoupled from the hub by pressing the release buttons to reversibly displace the cantilevered springs thereby moving the respective catches radially to disengage them from the circumferential recess, characterized in that each arm of a cantilevered spring has a length measured from its connection with the release button to its connection with the central support that is from about 0.75 to about 1.25 times the length of the radius of the circular hub, and in that each arm of a cantilevered spring further defines an angle of between about 35 degrees to about 50 degrees with respect to an axis normal to the central support and wherein an upper surface of the central support is located above the transition between the first portion and second portion of the release button. wherein the connector is coupled to the circular hub by catches that engage the circumferential recess defined in the side surface of the circular hub such that the connector is free to rotate completely about the circular hub, wherein the connector is decoupled from the circular hub by pressing the release buttons to reversibly displace the respective catches radially to disengage from the circumferential recess, wherein the connector is coupled to the hub by positioning the connector on the hub and depressing the connector until the catches engage the circumferential recess, wherein the connector is decoupled from the hub by pressing the release buttons to reversibly displace the cantilevered springs thereby moving the respective catches radially to disengage them from the circumferential recess, characterized in that each arm of a cantilevered spring has a length measured from its connection with the release button to its connection with the central support that is from about 0.75 to about 1.25 times the length of the radius of the circular hub, and in that each arm of a cantilevered spring further defines an angle of between about 35 degrees to about 50 degrees with respect to an axis normal to the central support and wherein an upper surface of the central support is located above the transition between the first portion and second portion of the release button.