Breathable Side Ports for Water Drainage and Comfort 100% Water-Friendly, 100% MUCKPROOF SRC Rated for Excellent Multi-Surface Slip Resistance Lightweight and Easy to Slip On/Off ASTM D5511-18 / ISO 15985-14 Inspired by the Muck Muckster collection, the big kid's Muckster Lite Clog is 50 percent lighter, offers independently verified SRC rated slip-resisting traction and provides excellent support and comfort for all-day wear. The Muckster Lite Clog is built from a high-performance, lightweight foam called Bio Lite which is ultra-durable and easy to clean. The upper features side ventilation holes for breathability and drainage for water and debris. The entire clog is constructed from Bio Lite which is than many other injection Shaped foams in the market. Bio Lite has been granted a Green Leaf certificate by Intertek, an accredited independent 3rd party testing facility, verifying that this product will properly degrade in . landfills.