Here is one well-engineered fly box with a substantial O-ring seal to keep the water off of your favorite flies. At least until you select one for action! The Large size has a great capacity for all of your flies. Inside you'll find our great EasyGrip foam which won't rip or tear while holding your flies securely. Boxes are made from polypropylene plastic with a streamlined shape, stainless hinge, ribbed surface for strength, long latch with double anchor points ensuring full closure, air pressure relief feature, and two lanyard loops.