Aquanite hopper

The Aquanite hopper is a members-only Old School RuneScape item — “An autoloading contraption made of aquanite bits. Slimy.”. Its Grand Exchange buy limit is effectively unlimited. Right now it buys at 400,003 gp and sells at 549,009 gp — a net margin of 138,026 gp (34.5% ROI) after the 2% Grand Exchange tax of 10,980 gp. High alchemy yields 4,800 gp.

To flip it, place a buy offer near 400,003 gp and a sell offer near 549,009 gp; the spread minus GE tax is your profit. Confidence figures are model estimates from live OSRS Wiki prices, not guarantees — flip responsibly.