Made from a lightweight, durable fiberglass-reinforced polycarbonate resin from Bayer known as Makrolon, makes it virtually break resistant. The pen uses Lamy's M21 refills, black, red, blue and green in a single pen. It is a perfect pen to own or gift to professors, teachers and people who carry multiple coloured pens. It uses the gravity mechanism to expel the desired colour code located at the top near the head of the clip. The brushed barrel feels great to hold and write with. 100% made in Germany. Lamy offers a 2 year global guarantee against manufacturing defect.