This permanent marker has a thin, 4mm felt chisel tip and contains alcohol-based pigmented ink. Perfectly pocket-sized, it is compact and portable so you can take it on the go easily.Details:Available in multiple colors4 mm tip size4" x 0.59" x 0.59" (10.16cm x 1.5cm x 1.5cm) marker sizeAlcohol based inkWaterproofConforms to ASTM D-4236