The Retro 51 Bamboo Ball Pen is made from Bamboo grown specifically for this purpose. Bamboo is the fastest growing woody plant in the world and is perfect for this purpose. It is grown in an environmentally sustainable way and with every pen sold a donation is made to the Arbor Day Foundation to rescue and protect rain forrest from clearing. A sensible sustainable material to make a pen with limited environmental impact with a positive of the benefit to the Arbor Foundation who are truly making a difference in saving the planet!!