The Siren 4 Thermo Mid Zip Waterproof features:

• Waterproof membrane seals out water and lets moisture escape
• Waterproof full grain leather and knit upper
• 100% recycled laces and webbing
• Heavy-duty, Waterproof, YKK medial zipper for easy on and off
• Bellows tongue keeps out debris
• Protective and abrasion resistant rubber heel and toe cap
• 100% recycled fleece lining
• 200 grams Primaloft Gold Eco Series synthetic insulation
• SOLARCORE Aerogel insole provides underfoot superior warmth while being extremely flexible and ultra-thin
• 100% recycled mesh footbed cover
• Cleansport NXT treated for natural odor control
• 5% recycled removable PU footbed
• FloatPro Foam midsole for lightweight comfort that lasts
• Vibram Icetrek outsole designed to provide the improved grip on very cold, icy, or snowy surfaces
• Vibram traction lugs specifically designed to increase traction and shed debris with each strep