Sanfew serum(4)

Sanfew Serum(4) is a members-only item on the OSRS Grand Exchange in the potions category.

In-game examine text: "A 4 dose Sanfew Serum."

It has a Grand Exchange buy limit of 2,000 every four hours, a high alchemy value of 180 gp, and item ID 10925.

View on OSRS Wiki

Sanfew Serum(4) shows an active flip setup with a margin of +198 gp and 143,809 trades over the last 24 hours.

At the buy limit of 2,000 every four hours, max profit per cycle is about 396.0k gp — high margin with healthy liquidity.