One of 2 designs from 1941 produced by Ostby & Barton of Rhode Island and used by dairies participating in the Superman Defense Club milk program. Ring top features various initials of milk company sponsor, in this case a letter “R.” Below the initial is a diagonal lightning bolt and below that an eyeball surrounded by accent lines. The brass plate snaps off from the base and the underside of the snap-off piece holds a paper sticker picturing and reading “Superman.” The paper has minimal microscopic wear but to the naked eye displays Mint and this is one of only two or three we've seen as nice in five decades. The top of the snap-off piece has outstanding NM luster. The entire ring base also has NM luster. Overall an outstanding NM example.