Large magnetic set for better position check. For 33 board, or 35 board, or A3 board, or A3 ECB. Magnetic set consists of magnetic pad and 2 magnets (one spare). After inserting the map under the film you can place the magnet on the spot in the map where you are right now. Self adhesive - you may or needn´t to stuck it to the board. Size of the magnetic pad is 2 cm smaller than the board size. Specify the board size in the "Note" at the end of the ordering process. Not possible to combine with Compass Extension accessories.
Videotutorial here.