- Attaching the MagSafe Battery Pack is a snap. - It automatically charges, so there’s no need to turn it on or off. There’s no interference with your credit cards or key fobs either. - At your desk and need a charge. Just plug a Lightning cable into the MagSafe Battery Pack for up to 15W of wireless charging. Short on time . - This portable charger is recommended to use with an Apple 20W or higher USB-C Power Adapter and an Apple USB-C to Lightning Cable (sold separately).