The Sharpie Twin Tip Marker is a versatile and reliable writing tool, featuring both an ultra-fine nib and a fine bullet nib for detailed tasks. Its bold black ink is permanent on most surfaces, including cardboard, photo paper, corrugated surfaces, wood, metal, sheets, stone, plastic, and leather. This 2-in-1 marker is perfect for precise writing, labeling, and creative projects, offering flexibility with its dual tips for meticulous detail.