Abstract: A plate-like housing is adapted to be secured to a wallet, or other pocket-sized valuable, and has formed therein a channel which is substantially transverse to the direction of the article or valuable withdrawal from a clothing pocket, or the like. A pair of slides are reciprocably movable in the channel and are spring-urged outwardly from the article in a transverse direction so that the slide ends are engageable with opposite sides of the pocket confines when the slides are in their extended or outermost positions. The respective ends of the slides each carry a pivotally mounted wing which cammingly engage the opposite sides of the pocket confines, thus increasing the slide dimension in the transverse direction, upon attempted withdrawal of the article from the pocket.