try these[1], they go between cards and prevent the one behind it from being read. 1: https://www.google.com/search?q=%E6%94%B9%E6%9C%AD%E3%82%A8%E3%83%A9%E3%8

try these[1], they go between cards and prevent the one behind it from being read. 1: https://www.google.com/search?q=%E6%94%B9%E6%9C%AD%E3%82%A8%E3%83%A9%E3%83%BC%E9%98%B2%E6%AD%A2%E3%82%AB%E3%83%BC%E3%83%89 https://www.google.com/search?q=%E6%94%B9%E6%9C%AD%E3%82%A8%...