TOP CHOICE FOR COLD DAYS - Enjoy winter activities to the fullest with the Therm-ic Set Heat Kit + C-Pack 1300; It comes with everything you need to keep your feet warm all day long this winter: 2 heat elements, 2 topcovers and 1 pair of C-pack batteries HIGH PERFORMANCE - Ultra-fine replacement heat elements integrate into any type of insole and diffuse constant heat for immediate well-being & optimal foot temperature; Self-adhesive textile lining covers the heating element and guarantees utmost comfort MAXIMUM COMFORT - Stick-on Therm-ic top covers deliver added comfort and refinish Custom, 3Feet and 3D insoles; The top covers come in one size and can be easily trimmed to fit your foot, ensuring a comfortable and secure fit LONG-LASTING WARMTH - C-Pack 1300 batteries provide consistent heat throughout the day ensuring your feet stay warm for up to 13 hours; Suitable for use with Therm-ic Insoles Heat Flat, Heat 3D & Heat Kit; Includes a USB charger; Wall charger NOT included MANUAL HEAT CONTROL - This insole battery includes 3 manually controllable heat settings via a single control button; An easy-to-use switch allows you to select from three different heat settings ensuring that you can customize the level of warmth to suit your needs