Slania’s love for boxing prompted him to engrave a series of twenty-three Heavyweight Champions of the World, all in stamp format. They span a period from 1889 to 1964. The first was the bare-fisted boxer John L. Sullivan, and Slania used his his own hands as the model for the Sullivan-portrait. The year mentioned on each of these labels is the year of the championship. The labels are numbered consecutively in the upper left corner. These portraits show remarkably well Slania’s outstanding skill of portraying people, and capture with his burin their nature and inner feelings.
Note: There exists plastic plate souvenir sheets, that can easily be identified because of their poor quality compared to the original steel plate prints.
The label depicting Slania as «World Champion» first appeared in 2005, shortly after his death. This design was created by Piotr Naszarkowski to fill the empty 24th location in the series of boxer stamps created by Slania in the 1960s.The label being highly symbolic, shows Slania with his 1000th engraving (2001) in his hand, and in the background the emblem of Guinness World Record book granted to Slania for this engraving being the largest engraved stamp ever issued. The «denomination» of 1000 refers to the 1000th engraving. In the context it must be remembered that Slania himself was an avid boxer and as such a great admirer of the world champions. The number «24» top right refers to label No. 24 of the original Slania-set.