The Thumbport allows greater balance in holding the flute. It is comprised of a C-shaped shell and a thumb-like extension. The Thumbport helps the player to place the right hand at an efficient spot and provides additional support.
The Thumbport guides the player's right thumb to support the flute at an angle. The force created at this angle is the sum of two partial vectors: one supports the flute from below, and the other counters horizontal rotation. The extension arm rests on the thumb gently, which easily prevents the flute from rolling backwards.