• Warm and comfortable insoles: made of 15 mm thick synthetic wool, soft and comfortable. • Humanized design: inspired by the shape of the human foot, with ergonomic cushioning. • Non-slip insoles: wool felt bottom layer that improves air circulation. • Stitching design: fluffy fleece and high-density felt insole, durable and reusable. • Thick replacement insoles: ideal for boots, slippers, and more. • Keep warm all winter, providing comfort and pain relief.