Awesome find!
There are some more UPS especially for small electronics:
ebay.com/itm/Mini-UPS-Uninterruptable-Power-Supply-System-with-POE-Current-Transfer-Function/183952535867
ebay.com/itm/Mini-UPS-Uninterrupted-Power-Supply-7800mah-12V-2A-USB-5V-1A-Output-GM312/383191878917
ebay.com/itm/1575192-Vultech-UPS30PW-DC-Bianco-Mini-UPS-30-Watt-Gruppo-di-Continuita-Portatil/401874780975
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It would work, but it’s not available anymore: “Currently unavailable”
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They sell it in germany:
ebay.com/itm/12V-USV-Mini-USV-unterbrechungsfreie-DC-Stromversorgung-12-V-22-W-2000-mAh/122971057294
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Sure:
Blitzwolf QC3 power bank 10000mAh BW-P3, fixed version
Blitzwolf QC3 power bank 15600mAh BW-P5
Miller ML202 V4
Ravpower Turbo+ RP-PB043 (20100mAh)
Soshine E4S
Thrunite C2 power bank and charger
Tomo Power bank M2
Tomo Power bank M4