True color reproduction. Outstanding acid-free ink is archival quality waterproof waterbased has no odor will not smear nor feather when dry and will not bleed through most papers. Use for graphic art sketching pen and ink illustrations awards freehand art calligraphy as well as general letter writing and legal documents. AP non-toxic. Set contains black pens in 3 sizes: .25 .35 .45mm. Contents subject to change.