Stylus

This stylus is used to write on the wax tablets used in the Middle Ages for taking notes or temporary writing.

The pointed end is used to incise the beeswax spread on a wooden tablet. The flat end is used to smooth the wax and erase the writing: it is the eraser...
The length varies with the size of the wax tablets.

This object has the same use as those used on modern touch-screen tablets and called, by extension, “styluses”.