Super-Knit Moisture-Wicking, Breathable Lining. Removable Orthotic Airflow Open Cell PU Insert With Moisture-Wicking Cover, Breathable From Toe-to-heel, Anti-bacterial, Anti-fungal and Machine Washable. Tempered Steel Shank. Welt Construction. ''Digger'' Oil And Slip-Resistant Rubber Outsole. Long Wearing Rubber Heel Cap.