Bead heads on flies have two tasks. The first task is to catch fish (metallic and gloss fisnishes) and the second task is to take your fly to the bottom, where it is most effective. HANAK Competition beads come in tungsten and brass materials to suit varying water depths.
Tungsten, with its specific weight of 18kg/dm3 (much higher than the 11.9kg/dm3 of lead), means that flies can be significantly smaller and leaner while maintaining the same weight. This means that flies can be more attractive to fish, especially those big ones in deep pools or fast water.