Question about HP Tilt Pen

Have a look at this link (Show all matching products).
https://store.hp.com/Switzerlan...

There are still a few details missing about the model. A Spectre x360 or a Spectre Folio? In addition, the model number should be followed by two letters after "13-....." and only then by the numbers. So it is difficult to say. It's best to look directly on the HP page, where the compatibility is indicated.