Inkzall jobsite markers feature clog resistant tips and the ability to write through dusty, wet or oily surfaces. The durable marker tips are designed for writing on rough surfaces such as OSB, cinder block and concrete and the ink dries quickly to reduce smearing markings, without drying out quickly when the caps is left off. Built-in hard hat storage clip. Clog resistant marker tip and fine tip. Non-toxic ink. Black.