Patent ID: 8221387

Claim:
A medical device comprising: a guidewire having a first diameter and a distal stop having a second diameter greater than the first diameter; an elongate tubular member having a proximal end and a distal end with a guide wire receiving lumen extending therethrough, a distal portion of the guidewire lumen having an inner diameter of substantially the same magnitude as the first diameter; and a tip disposed at the distal end of the elongate tubular member and having a distal end, a proximal end and a tip lumen therethrough, the tip having an elastic portion and a radially inextensible distal portion distal of the elastic portion; wherein the elongate tubular member is slidably disposed on the guidewire such that the distal end of the tip engages against the distal stop when the elongate tubular member is advanced distally relative to the guidewire; wherein the tip comprises an amorphous polymer and the radially inextensible distal portion comprises a locally crystalline section thereof; wherein the radially inextensible distal portion is a distalmost extremity; wherein when the tip directly contacts the distal stop and the elongate tubular member is forced distally relative to the guidewire, the elastic portion of the tip inverts inwardly and the radially inextensible distal portion enters an internal cavity within the tip.