@kempynat
If your computer supports an Active Stylus, your computer model will be listed in the Compatibility document along with supported Active Stylus / Active Pens.
I checked an additional source for the HP Stream x360 11-aa0xx models.
I do not find a Stylus for your pen. 
Things that are the HP Pen
Find a Stylus for your computer
First, find the computer's exact Model name:
HP Notebook PCs - How Do I Find My Model Number or Product Number?
Next, search the document for a compatible stylus:
HP PCs - Touchscreen Compatibility with Pen and Stylus
If there is an HP Active Stylus available for your model, it should be included in the document.
Additional information can be found in Advisory Documents.
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Dragon-Fur
