Tungsten is a dense metal almost twice the weight of lead and about 40% heavier than brass, but in a much more compact size. This makes it ideal for getting subsurface flies into the fish's feeding zone faster without the need for additional weight on the leader—which makes it harder to cast and easier to get your line tangled.
There are two situations where a tungsten fly is your best choice: When fishing heavy, white water pockets where trout will feed on nymphs churning around below the surface, and when stalking trout deep on the bottom during very cold or hot weather. In the latter situation, you really want your nymph to stay on the stream bottom.
We have a variety of tungsten beadhead nymph flies available online, all tested and approved by our on-staff fly fishing experts. If you have questions, or would like a specific recommendation, give us a call at 414-259-8100.