The Inogen One G3 External Battery Charger will charge your Inogen One G3 single and double batteries.If you are active and need to recharge multiple Inogen One G3 batteries simultaneously, then order an extra charger to help you charge more batteries as needed.Specifications:Includes charger, power supply, and AC input cord.Recharge Time: It takes approximately 3 hours to charge a fully depleted single battery, and approximately 6 hours to charge a fully depleted double battery.