A retaining device to secure a socket to an anvil using provided socket holes and anvil hole, including an O-ring and an integral projecting member extending inwardly from the O-ring, the projecting member having a cross-sectional diameter that conforms with the diameter of the holes in the socket and anvil. The O-ring, though integrally formed with the projecting member, is formed at a reduced cross-sectional diameter so that the overall retaining device can be stretched onto a wider range of socket sizes. The preferred projecting member includes a full-length crush gauge that is positioned in at least one of the juxtapositions between the socket holes and the anvil hole.