The plastic sleeves that we all get at work to hold our various ID badges honestly suck. So I found a solid file and made it modular to fit the combinations of cards that people may use. a single ID card is usually .80mm and a HID card is usually 1.75mm in thickness. For this print, there is a front and back plate that you will always need and then it's just finding the spacer you need for the middle (shown in red in the pictures)