This on’e a little more beefy than previous power packs I’ve recently looked at (I did sayI had a backlog). The Besiter 20000mAh QC3.0 Quick Charge Dual USB LED Display Power Bank is a solid-looking and only JUST pocket-sized battery pack able to handle type-C, micro-usb and full USB-S connections as well as being a Quick-Charge compatible battery pack.
The highest current output seems a little low for a large unit with a high capacity battery 2.4A at 5v down to 1.A at 12v (when doing QC3.0 charging),
The BST K6X comes with an on-off switch on the side (so no Raspberry Pi UPS function – but that is pretty much the norm) and a nice big LCD display on the front. The unit LOOKS big enough to support the 20,000maH claim and it is quite weighty – time will tell. It already charged my Pocophone F1 without breaking a sweat. The patterned finish you see in the photo is real, not a camera artifact. Quite nice.