Superman 1977 Kryptonite Rock Glow-in-the-dark original vintage, NEW old stock in Box, DC Comics Exclusive 1977 promotion from DC Comics, New "Old Stock." Expose to light briefly, green rocks then glow in the dark. Each box has instruction booklet. Rocks are mint and new; boxes are creased and pushed in from storage but graphics are bright. May be 1, 2 or 3 rocks depending on size.