Iron knife

Iron Knife is a members-only item on the OSRS Grand Exchange in the bars category.

In-game examine text: "A finely balanced throwing knife."

It has a Grand Exchange buy limit of 7,000 every four hours, a high alchemy value of 1 gp, and item ID 863.

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Iron Knife shows an active flip setup with a margin of +3 gp and 479,754 trades over the last 24 hours.

At the buy limit of 7,000 every four hours, max profit per cycle is about 21.0k gp — high margin with healthy liquidity.