Please refrain from purchasing if you are overly concerned about details. Purple 1. HAZUP insole: Promotes toe gripping exercise just by walking. 2. Easy-to-walk outsole design: Rolling shape. 3. Wide design for comfortable toe splay (equivalent to 4E/based on our standards). 4. Reflective material used on the heel to enhance nighttime visibility. 5. Mesh is used extensively for breathability. 6. Non-marking rubber used. 7. Easy to put on and take off with elastic shoelaces. Upper: Synthetic fiber/synthetic leather. Sole: Synthetic sole.