Patent ID: 8322051

Claim:
A self-adjusting stud, comprising: a first portion having a first retractability, wherein the first portion includes an impact-attenuating assembly having a hole therethrough, a plunger positioned to activate the impact-attenuating assembly when a force is applied to the plunger, wherein at least a portion of the plunger extends through the hole of the impact-attenuating assembly, and a tip that engages with the portion of the plunger that extends through the hole of the impact-attenuating assembly, wherein the tip is in a retracted position when the impact-attenuating assembly is in a first, unactivated state and the tip is in an extended position when the impact-attenuating assembly is in a second, activated state; and a second portion having a second retractability that is less than the first retractability, wherein the second portion surrounds the first portion; wherein the first portion and the second portion are substantially unretracted when the self-adjusting stud comes into contact with a surface of a first hardness and the first portion is retracted and the second portion is substantially unretracted when the self-adjusting stud comes into contact with a surface of a second hardness, and wherein the first hardness is less than the second hardness.