This small nylon clamp can discreetly hold a pencil by gently clamping to one of the tubes on your instrument. We were all taught to bring a pencil to rehearsal, and with this clamp, you will always have one at the ready. When used on a tuba, you can bury the pencil deep in the tubing wrap and no one will see. The soft material will not scratch or mark your instrument. At $2 each, you can afford one for each of your instruments. It can't hurt if every student in your studio has one of these.
Trombone players always ask, "Is there a medium size pencil holder for trombone?" Sadly there is not. The trumpet/French horn pencil holder is too small. However, if you don't mind the pencil holder being located on the large side of your tuning slide, this one will work for trombone. Depending upon model, that may affect your ability to place the trombone in its case, but we know it can work.