Quick Features - & 127777;& 65039; 3-Level Temperature Control (35-55°C) - & 9889; USB-Powered (5V/2.4A compatible) - & 128293; 30-Second Heat Activation - & 128170; Targeted Heating: Knees, Back & Waist - & 128737;& 65039; Built-in Safety Protection - & 129530; Machine Washable Product Description Stay warm and comfortable in any winter activity with our advanced USB heated thermal underwear. Designed for both men and women, this innovative base layer combines premium comfort with smart heating technology. Advanced Heating Technology - Rapid 30-second heat activation - Three temperature settings with LED indicators:   - High: 45-55°C (Red LED)   - Medium: 40-50°C (Blue LED)   - Low: 35-45°C (White LED) - Strategic heating zones: knees, back, and waist - 6-7 hours of continuous heat with 10000mAh power bank (not included) Safety & Comfort - Premium blend: 95% Cotton + 5% Spandex with carbon fiber heating - 5V safety voltage with overheat protection - Auto temperature regulation - Machine washable with protective features - Compatible with standard USB power banks Perfect For - Winter Sports: Skiing, Snowboarding - Outdoor Activities: Hiking, Hunting, Fishing - Daily Use: Walking, Running, Commuting - Health Benefits: Aids circulation, helps with joint stiffness - Medical Conditions: Suitable for Raynaud's disease, arthritis Specifications - Available Colors: Black, Gray - Sizes: S to 5XL - Season: Autumn/Winter - Power Source: Any 5V/2.4A USB power bank (not included) What's in the Box Choose from: - Heated Thermal Top - Heated Thermal Pants - Complete Set (Top & Pants) Care Instructions 1. Remove power bank before washing 2. Use laundry bag for machine washing 3. Avoid harsh detergents 4. Air dry recommended 5. Store in cool, dry place Usage Guide 1. Fully charge your power bank 2. Connect to USB port in pocket 3. Press power button for 3 seconds 4. Select temperature (Red→Blue→White LED) 5. Enjoy consistent warmth Note: Battery life varies based on temperature setting and power bank capacity. For optimal performance, use a 10000mAh or higher capacity power bank. Keywords: heated underwear, thermal base layer, USB heated clothing, winter sports gear, heated apparel, thermal wear, electric heating clothes, winter warmth, thermal protection, heated base layer Women's Tops Size Chart Size Length Shoulder Chest Hem Height Weight (lbs) S 21.1" 13.4" 31.5" 32.3" 59"-63" 88-99 M 21.9" 13.8" 33.1" 33.9" 63"-67" 99-121 L 22.6" 14.2" 34.6" 35.4" 65"-69" 121-132 XL 23.4" 14.6" 36.2" 37.0" 66"-70" 132-143 2XL 24.2" 15.0" 37.0" 38.6" 67"-71" 143-165 3XL 24.6" 15.4" 39.4" 40.2" 68"-72" 165-187 4XL 25.0" 15.7" 40.9" 41.7" 68"-72" 187-198 Women's Trouser Size Chart Size Length Hips Ankles Height Weight (lbs) S 36.8" 31.5" 4.4" 59"-63" 88-99 M 37.0" 33.1" 4.7" 63"-67" 99-121 L 37.6" 34.6" 5.0" 65"-69" 121-132 XL 38.2" 36.2" 5.4" 66"-70" 132-143 2XL 38.6" 37.8" 5.6" 67"-71" 143-165 3XL 39.0" 39.4" 5.9" 68"-72" 165-187 4XL 39.4" 40.9" 6.2" 68"-72" 187-198 Note: - All measurements have a tolerance of ±0.4-1.2 inches - These measurements are for reference only. Please refer to actual product measurements when possible.