Instead of the sane approach of specifying 5, 9, 12, 15, and/or 20 volts and the amperages, products insist on listing every model of device in existence instead.

Most will do 12V, but I always want to make sure it’ll power my laptop (20V) as well.

A big thank you to reviewers who post images of the actual products where it shows the relevant info in one short line on the labels:

e.g. PD Output: 5V=3A, 9V=3A, 12V=3A, 15V=3A, 20V=3A