With the Milwaukee inkzall marker set, you get reliable marking performance on any tough jobsite. The durable acrylic tip resists pressure without mushrooming and writes smoothly on rough, dusty, wet, or oily surfaces such as concrete, wood, OSB, plywood, metal, and plastic. Even after being left uncapped for more than 72 hours, the marker continues to write without drying out. The quick-drying black ink prevents smearing on smooth pvc and metal pipes. This convenient 4-piece pack ensures your cut lines and layout measurements remain sharp and legible every time.