I tried it with another single port usb-c charger (65w) and an apple usb-c charging cable and it worked with that. The packaging says to use a 30w (minimum) charger. I guess it needs 15+5+5 plus some small amount for the device itself.

I think it's great for overnight nightstand charging but if you want a fast 80% charge on your phone a dedicated charger would be better..

-David