On the left side of the coin, on a separate surface, a stylised image of Casimir the Great, from a plaque commemorating the foundation of Collegiate Basilica of the Birth of the Blessed Virgin Mary in Wiślica. At the bottom, on a circle-shaped surface, the image of the Eagle established as the state emblem of the Republic of Poland; along the rim the inscription: RZECZPOSPOLITA POLSKA (the Republic of Poland) and, following a separating pellet, the notation of the year of issue: 2015; below the Eagle, the inscription: 20 ZŁ and, below the Eagle on the right, the Mint mark: M/W. On the right side of the coin, a stylised image of the obverse of the grosz of Casimir the Great, with the image of a crown in the middle; the inscription around the crown, within two concentric circles: +KAZIMIRVS PRIMVS/+DEI GRACIA REX POLONIE.
In the centre, a stylised image of the reverse of the grosz of Casimir the Great, including a stylised image of an eagle wearing a crown; the inscription around the eagle: +GROSSI CRACOVIENSES. On the left side of the coin, partly covered by the image of the grosz, a fragment of the door of the Wawel Cathedral, with the letter K repeated, and an image of a crown above it. Along the right edge of the coin, from the top to the bottom, a semi-circular inscription: GROSZ KAZIMIERZA WIELKIEGO (Grosz of Casimir the Great).
- package – cardboard box
- certificate – yes
- number of subjects in the series: 7/20