[1/3 Scientific Bending Design]: 360bendable soleSegmented design according to ergonomics and kinematics Segmented design at 1/3 of the correct bend point. Facilitate the bending of the feet, facilitate the baby to walk, and reduce the burden before toddlers. [Size]: UK2: Foot length 11cm(Insole size:11.5cm),Recommend Age:6-12 Months; UK 3: Foot length: 12cm(Insole size:12.5cm),Recommend Age:12-18Months;UK 4: Foot length: 13cm(Insole size:13.5),Recommend Age:18-24Months;UK 5: Foot length: 14cm(Insole size:14.5),Recommend Age:24-36Months;UK 6: Foot length: 15 cm (Insole size:15.5),Recommend Age:36-48Months;Please carefully measure the length of your childs feet before purchasing the product.Tips:there may be an error of 0.1-0.3cm. Outer Material: Wool Sole: Rubber Closure: Pull On Material Composition: Mesh+Rubber Shoe Width: Medium