Copic Markers Y21-Sketch， Buttercup Yellow<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>Sketch markers - available in 358 colors and have 3 nib options</li><li>Refillable markers and replaceable nibs; compatible with copic air brush system</li><li>Alcohol-based ink is pemranent and non-toxic; dries acid free</li></ul></div><img src="http://ecx.images-amazon.com/images/I/41DPw8OLyZL.jpg" noproxy>