This is an Anker PowerCore 5,000mAh Portable Charger, Ultra-Compact 5K External Battery. Yes, it's brand new––I can't use it because I did something dumb: didn't check its compatibility with my phone before I bought it, and didn't keep the original packaging so I couldn't return it. Dumb! I did charge it up, though, before I found out....so I know it works.
If it will work for you, it's all yours! The Amazon listing says it's compatible with "iPhone 15/15 Plus/15 Pro/15 Pro Max, iPad, Samsung Galaxy and More"
New portable phone charger (North Boulder)
This offer has been gifted to someone and is no longer available.