This is a unused rain cover for an Oakley backpack or most other backpacks. It came with my sons pricey Oakley backpack but he never used it. It has water repellent fabric and a heavy duty drawstring. With drawstring not pulled the entire circumference measures 29' It fold up easily to place at the bottom of in a small pocket in the backpack for quick use if needed. It is lightweight. This cover is not fitted, it is just meant to be placed quickly around the backpack in bad weather. Place it on, pull the drawstring and place the backpack on your back or shoulder.