100% bamboo. Beveled edge. Recycled, unbleached carton printed with soy-based ink used for packaging. Bamboo is one of the fastest growing plants on the planet, and bamboo forests create 30% more oxygen than hardwood. We hope you will enjoy your new bamboo ruler while continuing to protect our planet. www.onyxandblue.com. Facebook. Twitter. Designed in Canada. Made in China.