Sperry's Classic Saltwatwer Boot in BIONIC materials. BIONIC materials are made with plastic recovered from marine and coastal enviornments. Each pair of Sperry Bionic shoes is made from an average of 5 recycled plastic bottles; Bionic Shaft upper with rubber duck toe shell; rawhide barrel lacing with rust proof eyelets for secure fit; side zipper for easy on/off; micro fleece lining and non marking lugged rubber outsole with wave siping for traction.