how do flexible pencils work?

Question

Like this one. https://www.connectad.net/990701-thickbox_default/flexi.jpg

I’ve tried to look it up but it’s still mindblowing how they are able to manage this.

Thanks!

In: 6

Answer 1

I had one when I was younger and it was a rubber pencil but the core graphite part that is “writing” was just a few inch long and not flexible. The flexible part is the rest of the pencil.