The FingerPort is a tremendous accessory for flute players of all experience levels. The Fingerport allows greater balance in holding the flute. It is comprised of a C-shaped shell and a thumb-like extension. The Fingerport helps the player to place the index finger at an efficient spot and provides additional support.
The flute has a circular tube. It is the source of instability. Try to lay a pipe on the floor and see how easily it rolls with any external force... The Fingerport is very simple - it provides a large flat surface for the left index finger to support the flute.