Personalized Coolest Trombone Player Youth T-Shirt. A snowman trombone player wearing a music note scarf with the text The world's coolest trombone player is a humorous music design for Christmas and the winter holidays. Let the good times roll in a durable T-Shirt that takes kids from school to play in an amazing array of colors. 5.0 oz., pre-shrunk 100% cotton. Seamless 1x1 rib collar.