Ansai Mobile Warming 7.4V 2.2Ah Lithium-Ion Battery powers all of your Ansai Mobile Warming heated clothing. Using extra batteries extends your outdoor journey and keeps you warmer longer.Compatible with Mobile Warming vests, jackets and glovesCan provide up to 10 hours of power depending on heat settingsLightweight constructionLED power indicatorsEasy push button operationFull Power Setting135 F; lasts up to 2.5 hours75% Power Setting120F; lasts up to 3 hours 50% Power Setting105 F; lasts up to 5 hours25% Power Setting90 F; lasts up to 10 hours