Markal DURA-INK® 55 Medium Taper Marker Black (Tub 20)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. Tub