These dual brush pens have a versatile and flexible nylon fiber brush tip on one end that creates medium or bold strokes by simply changing brush pressure. The fine tip on the other end is for smooth straight lines or writing. Water based ink blendable odorless non-bleeding. Acid free and non-toxic perfect for fine art techniques. Sold in a pack of six colors: light sand, burnt sienna, redwood, gray green, hunter green, true blue. Conforms to ASTM D4236. Imported.