Markal DURA-INK® are permanent, smear and water-resistant heavy-duty felt tip markers with versatile bullet tips (DURA-INK® 15 and 55) and chisel tip (DURA-INK® 25), and are used in a wide variety of industrial applications. They mark on a variety of surfaces including metal, wood, plastic, glass, rubber, cardboard, paper etc. MKL96237: DURA-INK® 25 - Chisel Tip.MKL96070: DURA-INK® 15 - Fine Taper Bullet Tip.MKL96078: DURA-INK® 55 - Medium Taper Bullet Tip.