A must upgrade parts for your Qidi X-Max Printer, or DIY your own printer. PEI with high temp adhesive: Custom designed PEI materials to make your print easy to adhere to the printing surface, flexible, removable. Kindly Tips: We have helped you stick PEI on the steel plate, use machine, so you no longer need to worry about bubbles. PEI compatible with all most filament, include PLA/ Carbon PETG ABS/ TPU/ Wood etc. Before printing, Please remove the protect film which stick on the PEI surface, so if you received package but found the air bubbles or Scratches, please don't worry, they are the surface layer, PEI will not be affected. Magnetic Base: high temp-resistant with high temp adhesive, easy installation and easy to remove. You also can cut it for any size. Steel Spring Material: steel, thickness about 0.5mm, positive and negative side can be reused.