When you are on your feet working for long hours, the Crocs Classic Work Clog gives you the comfort and features that work as hard as you do. Find Your Size: We recommend sizing down (e.g. if you are a 7.5, size down to a 7) Crocs Lock slip-resistant tread. Enclosed, round toe silhouette. Iconic Crocs Comfort. Meets EN ISO 20347:2012, OB, SRC. Meets ASTM F2913-11, CE certified. Pivotable, adjustable backstrap. Waterproof upper.