Flies with trailing hooks on flexible leaders do not work well with traditional foam fly boxes. Here is a novel idea. Rust-proof magnets grip the eye of intruder-style flies instead of the hook. A clean, simple and safe design for storing your large flies. Designed for Intruder-style files and other large flies. 18 rare earth magnets secure flies at the eye. Box is patterned after the large waterproof box series with clear lid.