I haven't seen those before but it looks like a single precut sheet of "blue painters tape" sized to the print bed. Does it have the texture of painters tape? I know the Flashforge printers we sell come with yellow Kapton tape preapplied to the bed and a roll of 3M blue painters tape In the box.

One tip with blue painters tape... clean the newly taped bed with rubbing alcohol before printing to get your prints to stick better. The tape I've used (3M) come with a waxy residue on the surface that, while good for painting, isn't so hot for 3d printing. You'll find your prints stick much better after the isopropyl cleaning