The backpacks are a decent size and can hold a lot of stuff. The straps on the back are adjustable as with all backpacks. You can get yours starting at $49.99 on sale for a limited time. I really like these backpacks and the front faces are very well done. You can in the images, I was sent the Nirvana style and a Boldface custom front face with a beautiful beach.
Click here for your own: https://www.boldfacegear.com/. There are also guitar bags as well with the same concept.