Abstract: A twist type locking pin formed from a single piece of wirelike stock having a U-shaped bend forming two sides, one side being bent to form an arcuate loop which terminates short of the other side and is bent at an angle to cross over the other side, the other side being bent to form an arcuate loop which lies in a plane perpendicular to the plane of the first arcuate loop, the end of the second arcuate loop overlying the one side, the second arcuate loop forming a bearing surface at the end of the other side, the second loop forcing the other side outwardly from the one side on insertion of the one side into a post, the other side producing a bias force which rotates the one side through 90.degree. when the end of the other side clears the post to pivot the locking pin to a locking position.