Print stickers improve adhesion of filament to the print bed and can be used in combination with all filaments. Leapfrog uses a tempered glass plate for the print bed to ensure the print bed is strait and is not affected by a temperature increase or decrease. The glass plate is very smooth. To ensure the filament sticks to the bed it is necessary to use print stickers. Print stickers will last for multiple prints. In the Leapfrog Creatr Manual you can see how to replace your print sticker.