The polymer coating used in the core of Kei Coat prevents the marker tip from breaking, drawing uneven lines, or staining rulers, which may lead to staining the surroundings and the tips of other pens. Highly resistant polymer coating protects the core and greatly reduces frustration caused by pen tips. Accurate and neat marking is guaranteed in every use. The resin coating on the tip of the polymer-coated core prevents the marker tip from breaking and from staining rulers. The marker features a plastic core specially developed for pigment ink. Unlike the easily breakable core used in the past, this new tip can withstand strong pen pressure. · Eco Mark certified product（Kei Coat）