Marks on almost anything: metal, plastic, printed circuit boards, glass, wood, paper, leather and textiles * Writes on any surface porous or non-porous, rough or smooth, wet, oily and dry * Marks are permanent they won"t chip, peel, fade, or rub-off, they withstand heat and weathering under adverse conditions * Unique precision valve accurately meters flow, so the right amount of paint passes through the tip * Mark is approximately 1/8" wide