Abstract: A pair of coiled springs are mounted in tandem in a housing with their adjacent ends extending radially for retention in a housing permitting slight radial movement of the adjacent ends. The outer ends of the springs extend radially and are axially and circumferentially spaced apart and retained in the housing for slight circumferential movement. The outer ends of the spring are moved by tensioning them in opposite directions to increase the inner diameter of the annulus formed by the springs to receive a shaft upon which the springs tighten when the spring ends are released from tension.