Mid calf boots are boots that cover the ankle and lower leg up to the mid-calf. Mid calf boots can be made of any variety of materials, colors or styles.
About TPU:
TPU, or Thermoplastic Urethane, is synthetic material used in the footwear industry to manufacture shoe outersoles and as an added compound on the midsole to prevent overpronation. TPU soles generally provide enhanced slip and abrasion resistance as well as durability.