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Shark gloves are a reward that can be purchased with 200 tokens from the Fist of Guthix minigame. They require a Fishing level of 90 to wear. When worn, the gloves grant an additional 100 Fishing experience for every shark caught. This effect lasts for the catching of 1,000 sharks, after which they crumble to dust.
The experience gained from this item works additively with the double experience from using a volatile clay harpoon (or Sacred clay harpoon) from stealing creation. With both shark gloves, and a volatile or sacred harpoon equipped, a player receives 320 xp per shark caught. You can only get them from Fist of Guthix. You are not able to sell the items from Fist of Guthix back for tokens.