Powerology 10000mAh MagSafe Power Bank with Built-in Wall Charger, 35W Power Delivery, 4-Device Charging, 15W Wireless Output, Built-in USB-C to USB-C Cable - Black The Powerology 10000mAh MagSafe Power Bank with Built-in Wall Charger is the best option for portable charging. This compact power bank offers quick charging for up to four devices at the same time, thanks to its strong 35W power delivery.