Mens X X-Large 15+ * Womens 16+ * Has a semi-rigid strap that pulls the toes upward and the foot into a slight dorsiflexion position * This gently stretches the plantar fascia so it may heal * The combination of the thermal properties that help reduce inflamation and the stretching of the plantar fascia while sleeping may aid in the treatment of Plantar Fasciitis * Non-slip Safety SoleTM rubber grip bottom helps prevent slipping *