These 8" (20 cm) Patina Color Bamboo Double Points have precisely tapered, hand-crafted tips. They are made of Moso Bamboo which is the largest and strongest bamboo out of over 1,000 different species. The size is permanently laser imprinted on each needle. The Patina color is obtained with thermal heat. Size 4 is perfect for knitting the bottoms up pattern of the Knitted Knockers with Rowan's Cotton Glace yarn!