So, in December 2019 I started crafting my own thumb rests as I was getting issues with tension in my hand, especially on the bass trombone. They are thicker and the thumb lies in a custom shaped thumb "bed" which positions the thumb in a natural position. So basically, I don´t have to force my thumb into a position that potentially creates tension. What began as a simple idea soon became a new hobby for me.
Especially when the Corona situation hit, I experimented with different shapes and sizes not only to help me get rid of the tension in my hand, but also make my trombone(s) a little fancier 
I haven´t felt any tension in my hand since then.Here is a selection of what I´ve been working on so far !
The darker one is a custom model I crafted for a friend who has difficulties to keep the thumb in one place.
