M Revel IV Chelsea Black NONE Footbed: The classic Birkenstock footbed

Footbed: The classic Birkenstock footbed - features pronounced arch support

20% lyocell upper

Steel shank for arch support

Brim has a shaping wire and a removable fur ruff to protect your skin from harsh winds

anti-fatigue removable footbed

M Revel IV Chelsea Black NONE Footbed: The classic Birkenstock footbedFeatures Original Fit has generous space across the forefoot for toes to splay Heat Trapolator technology: Three layers of heat trapping materials underfoot 200g of KEEN. WARM Recycled P. E. T. insulation rated to 25F 32C Elastic gore for easy on & off Compression molded foam midsole for cushioning Thermal Heat Shield insole captures warmth KEEN. POLAR TRACTION outsole for better grip on snow and ice 5mm multi directional lugs for traction Stability