This is a pen / pencil / art brush attachment for the great Personalized Cuff Utensil Holder by Volksswitch. It's a mod of the Size Adapting Pen Clip by Chang Cai that I merged with the Utensil holder's dovetail bracket using Tinkercad.
Included are the hand mounts created by Volksswitch - measure the circumference of the palm to find the correct hand mount.
We are using this to help people with limited hand functions such as Mr. Pisit as seen in the photos.
PLA for holder, TPU best for hand mount