I’ve got my 9 year old daughter’s specialized hotrock with a wierd looking bb on it from before my bike knowledge e started. It’s not a cartridge type.

Looking for a 165mm Crank set. No luck yet. Anyone know where?

I have just bought a hotrock as a refurb project and have the same issue, interested if anyone has changed the BB on a hotrock.

It’s just a traditional old bb with a fixed cup on the drive side and an adjustable cup and lock ring on the left hand side
You can just adjust play out of it or replace the bearings very cheaply

Or just remove it and replace with a shimano square taper bb of the same length ( much better option)
Check out Sheldon browns web site or parks to see how they go together