Amazon.com: Made for Amazon Battery Base, in Black for Echo Dot (4th generation) Not compatible with previous generations of Echo or Echo Dot (1st Gen, 2nd Gen, or 3rd Gen). : Everything
Amazon.com: Amazon Basics Ultra-Portable Fast Charging Power Bank Battery, USB-C, 20100mAh with 18W PD and two 12W USB-A Ports for charging iPhone, Samsung, iPad, and more : Cell Phones & Accessories