Made of eco-friendly tungsten alloy material, 95% high density tungsten and gilded on the surface. Stable performance, anti-corrosion, anti-rust. Tungsten is 60% heavier than lead and 240% heavier than brass. The color is better, fast sinking, satisfy all your flying tying needs. If you want to weight a nymph without making it bulky then tungsten are the beads for you. The beads can used for beachhead patterns like Nymphs, Evil Weevil, Wooly Buggers, Copper John and countless other flies. Color:Gold/Silver/Copper Specification: Material: Tungsten Alloy Diameter 2.5mm / 0.10inch; Weight: 0.112g Diameter 3.0mm / 0.12inch; Weight: 0.203g Diameter 3.5mm / 0.14inch; Weight: 0.300g Diameter 4.0mm / 0.16inch; Weight: 0.403g Color: Gold,Silver,Copper Package Includes: 20 Pieces Slotted Tungsten Beads