Goblin mail

Goblin Mail is a free-to-play item on the OSRS Grand Exchange in the other category.

In-game examine text: "Some brown armour designed to fit goblins."

It has a Grand Exchange buy limit of 15 every four hours, a high alchemy value of 24 gp, and item ID 288.

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Goblin Mail shows an active flip setup with a margin of +24 gp and 2,901 trades over the last 24 hours.

At the buy limit of 15 every four hours, max profit per cycle is about 360 gp — high margin with healthy liquidity.