Karhu Men's Flow4 Trainer Synthetic-and-mesh Moisture wicking collar liner and dual-pronged memory foam heel provides dry and comfortably locked EVA padded lasting board under sock liner for added cushioning Lightweight, breathable near seamless one-piece air mesh upper Directly-placed EVA fulcrum to assist in efficient transition through the gait cycle Injection-molded, wearable EVA midsole for lightweight performance, traction and durability