Birchwood Casey Aluminum Black Touch-Up Pen-15121

Model Number: 15121. The pen does not have black "ink" or "paint" in it and the tip will not be black. The tip will remain white because the liquid is clear and very thin. The pen doesn't dye or paint the aluminum, it causes it to turn dark gray or black (may require multiple applications) via a chemical reaction with non-coated aluminum.

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