I’ve probably seen more USB battery packs than 99.9% of people living on this Earth, but I’ve never seen one like the ZeroLemon ToughJuice before. You get 30,000mAh of juice, five (!) USB ports, including a Quick Charge 2.0 port and a USB-C port, and a ruggedized exterior.
It’s niche, but at $50 (with code 7BUYTGVU), it’s not all that expensive for a 30,000mAh power bank, let alone one with so many features.
Aukey has an identically sized battery pack for $40 (with code QCPOWER3), and with Quick Charge 3.0 instead of 2.0, but it doesn’t have quite as many ports.