I usually gift this two-pack because everyone seems to have multiple bathrooms these days and you can try out both the 7" and the 9", but they have a 7" with a taller converter as well as many more attractive versions now.
They have a ridiculous explainer video:
It's become really mainstream and there are now travel versions and classy wooden versions, etc.
Note: I have a friend who feel very strongly that the right squatty potty is one that really does tuck all the way under the toilet and just pulls out when you need it. I actually think that the manufacturers agree and the “original” is actually a slimmer, more petite, version than the one I sent around when I found out about it. So if you were an early adopter and you find it sort of “in the way,” it might be time to upgrade.