This is a really good bag. I use this bass trombone bag for my tenor trombone mutes - which means I can put all of my mutes there! I can fit both cup, straight, harmon, bucket and the little plunger!
Inside of the bag, there are two removable "walls", which means that if you only want to have three mutes with you, they do not get any contact with each other! And hey, most often you do not need more than three mutes at a time either!
Sometimes, when I am going away over the weekend to play somewhere, I use it to pack both my mutes and my clothes in there. It is very good and have got space for sheet music too.
You can choose if you want to carry it by hand or with the shoulder strap.