RFID blocking card holder is made of ABS case and inside aluminium layer ,normal size is 90*60*4mm and customized size are available .You can engrave logo , silk screen logo or spay indicated color for whole body .It has aluminium layer inside so can block or stop RFID signal when we take RFID cards enter electromagnetic field .You can chose good RFID blocking products according to your need or different application .Zhixin has many kinds of blocking RFID products and we sure one of products can right for you.