Neoprene
Made in USA or Imported
4 mm neoprene provides comfort and flexibility, along with excellent waterproofing, shock absorption and heat retention properties; adjusts to the shape of your feet to resist blisters and chafing

Guarden Rubber Toe and Heel for Durability and Extended Wear
bioDEWIX Footbed Insert Topcover with NYZM for Odor Control and Moisture Management
Comfort Range: Sub Freezing to 65°F / 18°C