ecoTWX material upper; Nano Composite Safety Toe meets or exceeds ANSI standards ASTM F2413-18 M/I/C EH; As a migration from traditional nylon lining, ecoTweed Lining features material made with 100% P.E.T. plastic bottles; Nylon laces provide a secure fit; Elastic gore tongue panels provide option to wear shoe as a slip-on or lace up; Removable, moisture-wicking, antibacterial, and machine washable footbed