Pokemon Center 2018 Saiko Soda Campaign Pikachu & Eevee Train Pass Case. "Saiko" means "best" or "awesome" in Japanese. It was only sold at the Japan Pokemon Centers in May, 2018, for a very limited time and in very limited quantity, during the Saiko Soda campaign. It is intended to be a train or bus pass case. When you ride the trains or buses in Japan, most people have a magnetic pass (like a credit card) that they use instead of buying tickets. They swipe it over the gate entrance and it takes the money out of your card balance. If you look at the back of the pass case, there is a window to put your train or bus card in. It has a strap so you can attach it to your bag, purse, etc.