his is a great medium-large sized fishing sling pack for fly fishing with a lot of great features that make it very convenient. Of course it is designed to carry all your regular gear but it also can carry a fly rod while you hike, and big enough to carry a lunch with your gear to make a great day of fishing even better. 
Water-Resistant Material
With the ripstop honeycomb polyester with EVA lined inner walls this bag repels water nicely, only a little bit can slip in through the seams. If you take a quick fall in the water not much of any will get in the bag, I know from personal experience with this bag. 
Comfortable Design
Very Comfortable to wear with a breathable padded shoulder strap and back.
Medium-Large 10 Liter Size 
Large enough to fit lots of gear but not overly bulky to where it gets in the way. The pack size is about 13" tall x 9.5" wide x 6" deep. 
Large Main Compartment
Has a Large Main Compartment for lots of fly boxes, gear or even a lunch. Also has a divider and several pockets to organize gear.