We like the Umpqua UPG Silicone Essential Fly Box for its compact storage and waterproof construction. The box features a bombproof shell that's also waterproof if submerged in three feet of water for up to 20 minutes, keeping our flies dry and rust-free. It holds a wide range of dries and nymphs with a FlyTrap insert that allows for great storage of fully hackled flies.