Quote Originally Posted by Holly View Post
why does one have 110V and the other have 120V? Does that matter?
No, it doesn't matter.

Generally, these transformers will give you half the input voltage. The UK used to have a 240 volts mains supply and the rest of Europe was 220 volts. We have now standardised on 230 volts across Europe and I think Australia is 230 volts as well.

What this means is that you will probably get 115 volts out of both of them. A variation of ten volts either way on the mains supply is not uncommon and is nothing to worry about.