The Mighty Marker DG is a heavy-duty, truly permanent, ketone-based, xylene-free paint marker. Ideal permanent identification of parts subject to industrial degreasing solvents, and other extreme conditions. The Mighty Marker DG won't rub off slick surfaces. Takes 25 seconds to dry! Resistant to most coolants and cutting fluids. Permanent ink writes on smooth non-porous surfaces such as metal, aluminum, steel, and plastics. Marks withstand dirt, oil, grease, extreme weather conditions, industrial solvents, and alcohols.