Tighten the Mounting Nut with a Basin Wrench

1. Clear all items from under the sink to ensure full access to the mounting hardware. 2. Use a flashlight to locate the primary mounting nut on the underside of the sink deck. 3. Position a basin wrench around the nut. 4. Rotate the basin wrench clockwise to tighten the nut until it is snug against the sink basin. 5. While tightening, have an assistant hold the faucet steady from above to ensure it remains centered. 6. Verify the fix by rotating the faucet handle; the fixture should no longer rock against the sink deck.

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