A blood draw device for delivery of a probe into a patient's vascular system, the blood draw device including an introducer body having a proximal end and a distal end, and an actuator. The actuator is displaceable along at least a portion of the introducer body, and the actuator is operably coupled to the probe to advance and retract the probe based on direction of displacement of the actuator. The blood draw device also includes an advancement stop member, wherein the advancement stop member is displaceable along at least a portion of the introducer body and is configured to selectively limit travel of the actuator along the introducer body.