DCtattoo - Tattoo Stencil Thermal Carrier Sleeve, DO NOT be fooled by cheap imitations on the market. 
These are manufactured from thick robust acetate and high temperature sleeve tape! Used by artists worldwide! 

This thermal acetate carrier is designed to work in conjunction with thermal copier tattoo stencil carbon paper and thermal copier machines. Slip the stencil paper into this carrier sleeve to aid it through the machine for a smoother, more thorough stencil transfer.  This makes the process a lot easier & smoother. Suitable for use with A4 stencil carbon paper! These can also be used hundreds of times before they wear out!