This bag is for flutes up to 18" and the bag is 4 1/4" wide and is crafted by Native American  Artist Willie Jane Ross, Navajo. 
The bag actual length is 19".     Kokopelli, sun pattern

These are wonderful cloth fabric bags that are thick, padded and have a liner in them.

A flute bag will help protect your flute from sunlight, dust & damage. 
It also breathes and will allow your flute to dry out after use.