Tungsten putty that is applied, adjusted and sinks quicklyThis charcoal-colored nontoxic, Tungsten-based product is biodegradable and reusable, making it an environmentally friendly alternative to split shot and other lead-based weight. The weight and depth are easily adjustable, to make sure that a nymph always finds the bottom. -Tungsten putty weight-Non-toxic-Non-lead-Reusable-Charcoal color-Can be used as temporary bead head for nymphs-20 grams