Single cell 21700 powerbank?

EDC Gear for Flashlight Carriers USB Power Devices
2

Acebeam makes a model# ACEBEAM-IMR21700NP-510A-USB for $21.90, as seen here: ACEBEAM-IMR21700NP-510A-USB

I own one, and can confirm it works as a 5000mah battery bank. It also functions, but not internally charge, in my Olight Seeker 2 Pro.