Sinew

The Sinew is a members-only Old School RuneScape item — “I can use this to make a crossbow string.”. Its Grand Exchange buy limit is 13,000 per 4 hours. Right now it buys at 113 gp and sells at 113 gp — a net margin of -2 gp (-1.8% ROI) after the 2% Grand Exchange tax of 2 gp. High alchemy yields 1 gp.

To flip it, place a buy offer near 113 gp and a sell offer near 113 gp; the spread minus GE tax is your profit. Confidence figures are model estimates from live OSRS Wiki prices, not guarantees — flip responsibly.