@variablepulserate I think this is the one, https://www.amazon.co.uk/ELECJET-PowerPie-20000mAh-Portable-Compatible/dp/B081S471NN/ref=sr11?crid=37KZOK6JWIYJZ&keywords=ELECJET+PowerPie%7CUSB+C+Power+Bank+45W&qid=1641181795&sprefix=elecjet+powerpie+usb+c+power+bank+45w+%2Caps%2C745&sr=8-1 - the entry in the Amazon Oz store is different but the device looks identical.
It contains two batteries of 3.7v @20,000 mAh but the actual output is 13,500 mAh.