1.25" diameter by about 3/8" thick with finely detailed illustration on top of a boy scout giving three-finger salute. Underside has hexagonal nut on a screw and this holds a small piece of metal which joins the brass cover to an aluminum base. When piece is opened, there is an aluminum compass disk with a small hole on the underside and this fits on the tiny point extending from the threaded screw that held the nut. Interior of compartment also has blank lines for filling out owner's address and telephone number. Neat construction and with beautiful high brass luster. We believe from the late 30s. Mint appearance.