Normally that we use PET silver (metallized or color) for make Hologram security only one layers and then to embossed hologram . Anyway, some customer order case that they want something specials by printing or release function. So, the materails that we cannot use only one layer to do bec. some fuction that will be interfere or by tecnical use that we cannot work. That mean we important to coated more than one layer which alsogood for security.
2 layers stickers
This one is also 2 layers sticker because we need after first layer removed than can look our QR code for customer scan and use the passward no. So, it important to have other one layer for printing.
this one is 3 layers sticker