This heavy metal premium is 2.25” long and 5/8” thick issued with either brass or aluminum outer case (both are brass on underside) and both versions are included in this lot. These came from Derby Foods Inc., makers of Peter Pan Peanut Butter, in 1949. The premium is designed with owner’s personalized serial number on the upper right. The brass version has number “146030.” The aluminum version has relatively low number “20915.” Top surface of each features a decoding wheel plus opening to serve as a magnifying glass. Right side edge has opening with internal red wheel which can be used as an ink stamp for individual alphabet letters. One side edge has images of Sky King’s plane “Flying Arrow” and his horse “Yellow Fury.” Opposite side edge serves as a ruler. Underside of the piece has full figure of Sky King alongside his initials “SK.” One of the most complex decoders of all time and extremely well made. Brass version may have had tarnish cleaned off but displays bright and clean with the appearance of original luster. The aluminum version is Exc. One of the most complex devices to include a decoder.