Micron Pigma Pens contain pure black pigment in a felt tip! Waterproof and chemical proof with archival PH neutral ink.. They are excellent for drawing, graphics, documents, outlining and lettering work. For best results spray with a matte varnish after using so that the ink won't smear if varnish is brushed on. The larger the number the thicker the line.
Note: When not using these pens ensure that the cap is on tight. These pens have a felt tip so remember not to press too hard or the tip may bend causing ink flow to stop.