Fit & Design: Machine washable gentle cycle Powerful Tri-Zone heating system includes 3 built-in heating panels, strategically placed on the chest and upper back to warm your core body temperature Touch-Button Control Technology (3 settings) 4 LED power indicators display power bank battery life Zip front Battery Voltage: 5-Volt Power System: 2 Amp 100% nylon exterior 100% polyester interior How To Use: Charge Up- Fully charge power banks with provided charger kit. Plug-In- Connect the power bank to USB plug located in the pocket. Turn On- Press and hold touch-button control for 3 seconds. Press touch-button again to adjust the temperature. Estimated Heating Times: High (Red): 130F - 2+ Hours Medium (White): 110F - 3+ Hours Low (Blue): 90F - 4.5+ Hours Includes: ActionHeat Vest Liner ActionHeat 5V Power Bank (6000mAh) USB Charging Cord