KnitPro's repair hooks are made up of Laminated Birch wood in 3 different sizes to match your needs. Size : 3.50mm,4.50mm and 5.50mm Laminated Birch Wood Repair Hooks Laminated birch wood repair hooks Hook on one side and needle on the other Convenient size for easy storage Repair fallen and dropped stitches with perfect ease Must have accessory for all knitters and crocheters