The fastest and easiest way to touch up nicks and scratches is with a simple easy to use Presto Gun Blue Pen. It penetrates hard steel instantly and gives a durable blue black finish that will not rub off. Use like a marking pen for one coat coverage on non-stainless steels.
Specifications:

Type	Gun Blue
Size	1/3 oz
Quantity	1
Bristle Type
Length
Includes
Material	Felt
Tip Feature
Battery
Thread Pattern
Protects
Suitable For	Firearms
Eco-Friendly