Imported from Japan. These Sumo trading cards are based on the March, 2016, rankings. Each pack contains 5 random cards. The complete set has all 42 top division (Makuuchi) wrestlers, 18 wrestling action cards, 12 seasonal sumo word cards (one for each month), and several up and coming wrestlers for a set total of 81. See the scanned checklist for details (which are in Japanese). There are also 9 different autographed cards included randomly across every few boxes (24 packs per box). Most of the text on the cards is in Japanese, however, the wrestler's English language name is also on the card for those of us who don't speak Japanese.
Yokozuna for this series are Harumafuji, Hakuho, and Kakuryu.
Ozeki are Kotoshogiku, Kisenosato, Goeido, and Terunofuji.
Sekiwake are Yoshikaze and Toyonoshima.
Check out this link for the Makuuchi rankings from March, 2016, for a complete listing of all top division wrestlers.
Please note that sometimes this series is referred to as "Aya" instead of "Irodori". The packs are marked "Irodori".
Happy Collecting.