"W" refers to Women's and not Wide sizes
Features Crocs Lock technology which is slip-resistant and tested to ASTM F1677 standards
Odor-resistant
Product Description
Get all the comfort of Crocs in a mary jane style slip-on Crocs Lock slip-resistant sole is tested to ASTM F1677 standards Lightweight Croslite material footbed provides all-day comfort Enclosed design made of lightweight Croslite material Footbed circulation nubs Enhanced arch support 1/2" heel height Available in whole sizes only, half sizes order the next size down
Source:
http://www.crocs.com/
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