An elongated medical device includes a core element, a polymer member, a closure element, and a permanent magnetic element. The core element may have a distal region including a first region with a diameter greater than a diameter of a second region, the second region distal of the first region and terminating at a core element distal end. The polymer member may be circumferentially disposed about an entire length of the core element and extending distal of the core element distal end. The closure element may be affixed to a distal end of the polymer member. The permanent magnetic element may be disposed along the second region proximal to the core element distal end, and may include a plurality of permanent magnetic elements spaced apart along the second region.