The Samsung external battery pack can store up to 9, 000 m Ah of power, enough for up to three full charges of most Samsung smartphones & one full charge on most tablet devices. Its small size makes it a great back up for anyone who spends time regularly out of the office or traveling & are unable to access a power point. Always know your devices recharge status with the battery pack LED status indicator: red indicates the smartphone battery is being recharged, while green indicates that the battery is fully charged.