Bottled storm

The Bottled storm is a members-only Old School RuneScape item — “A violently shaking container containing the furious power of the sea.”. Its Grand Exchange buy limit is effectively unlimited. Right now it buys at 2,783,728 gp and sells at 2,940,000 gp — a net margin of 97,472 gp (3.5% ROI) after the 2% Grand Exchange tax of 58,800 gp. High alchemy yields 4,800 gp.

To flip it, place a buy offer near 2,783,728 gp and a sell offer near 2,940,000 gp; the spread minus GE tax is your profit. Confidence figures are model estimates from live OSRS Wiki prices, not guarantees — flip responsibly.