I bought 4 of these after I saw a Trombone player with one clipped onto his F/Bb Tenor Trombone. He had it above the bell, opposite tube to the shoulder/neck bar. I thought it was really cool and decoded to do it too. I have it on both my small bore Jazz Tenor and F/Bb tenor. Two different bore sizes. I clipped it on a narrower part and moved it downwards towards the bell without forcing it to go lower than it naturally can go. It stay on well and holds the pencil well also. It makes it so much better that clipping to a music stand or having a pencil loose. It is hidden when in playing position but if you want your pencil to blend in then maybe get a colour that doesn't stand out.