I believe these are clear files distributed at Yakult Swallows fan appreciation days or games. This is a set of 7 types and 8 sheets, as shown in the first image. 2001 Championship Akinori Iwamura & Ryota Igarashi Norichika Aoki: Batting Champion, Rookie of the Year, etc. Norichika Aoki: Stolen Base Champion Shinya Miyamoto Shohei Tateyama Kazuhisa Ishii These are unused, but please refrain from purchasing if you are sensitive to the condition, as they have been stored by a private individual.