Check the listing for details. Birchwood Casey Gun Bluing Super Black Touch Up Pen Flat Black 1/3oz. Color: Multicolor, Condition: New. Listed at 10.49 USD. Birchwood Casey Gun Bluing Super Black Touch Up Pen - Flat Black Birchwood Casey Super Black Touch-Up Pen Flat Black Effective touch-up for nicks, scratches and worn areas of black anodized aluminum or black painted surfaces. Pen contains a fast drying lead-free paint for use on highly polished and matte finished alloy guns. Use like a marking pen. Chisel point felt tip.Birchwood Casey Gun Bluing Super Black Touch Up Pen - Flat Black Birchwood Casey Super Black Touch-Up Pen Flat Black Effective touch-up for nicks, scratches and worn areas of black anodized aluminum or black painted surfaces. Pen contains a fast drying lead-free paint for use on highly polished and matte finished alloy guns. Use like a marking pen. Chisel point felt tip.