NIGERIA: 50 Kobo (ND 1973-78) in blue and purple on multicolor unpt with Central Bank of Nigeria building at center. S/N: "L/21 519477". WMK: Heraldic eagle. Signature #10. Inside holder by PMG "Gem Uncirculated 66 - EPQ". Top grade in PMG. (Pick 14g) & (Spink CBN B13g).