InkZall™ jobsite markers, which include a clog-resistant tip, allow you to write on dusty, wet, or oily surfaces. The durable marker tip is designed for writing on rough surfaces such as OSB, cinder block, and concrete. The ink dries quickly to reduce smearing and rub-off marks, without drying out quickly when the cap is removed. For added convenience, InkZall markers have a built-in hard hat clip, for quick storage and access.