Circa - 806 (Tan/Brown Synthetic Leather) - Men's: Part of Circa's new advanced performance series. New fusion grip rubber features a unique compound which is super sticky and greatly improves traction on grip tape. Ciba(R) antimicrobial inside lining material. C Unit dual air chamber cushioning system. Molded TPR lace protection. Removable ankle strap. 2 layer footbed. Waffle tread outsole. Stroble construction. Tan/Brown is a vegan shoe no animal products were used.