Kingfisher Ultra Slim 18 Compartment Magnetic Back Fly Box Magnetic compartments are great for frequently used and/ or bigger flies, this aids in keeping your flies from being lost in the wind Super thin and strong, made of high grade tough clarified polypropylene, packs light, but will hold up to a real beating Strong, secure snap tight latch closure that won't accidentally open in your pack or vest, clear lid to see your flies easily This box is divided into 18 magnetic compartments, the most efficient storage for its size 7" x 4" x 1/2", flies are for display only