Please Note: Colors may not be accurate due to differences in monitors and the Sizes may not be the Actual Sizes. Item Name: SKETCH Y21 BUTTERCUP YELLOW MARKER Item Number: CMY21-S Alcohol-based ink. Acid Free on most surfaces. Permanent & Non-Toxic. Guaranteed 3 year Shelf Life and Color Consistency. Refillable. Replaceable Nibs. Features Medium Broad & Super Brush Nibs.