These are Yo-kai Watch medals. There are 18 in total: Master Nyada, Gabunyan, Jibanyan (2 types), Ichigonyan, Jetnyan, Darknyan, Buchinyan (2 types), Jibanyan S, Robonyan F-type, Robonyan, Walnyan, Masked Nyan, Sailornyan, Kijinyan, Fuyunyan, and Momotaro Nyan. My child used these, but they no longer play with them, so I'm selling them. The use of the QR codes on the back is unknown. Please check the condition of the items in the images. Please understand that these items were used by a child before purchasing.