Right. That was the thing. They're 50/60hz based on location. I know something was different but I misremembered.
For the US, they use 240v split phase. The secondary on the transformers have a middle tap, called neutral, so if you go from line to line, you get 240v, if you go from either line to neutral, you get 115/120v approximately. The benefit to it is that you can use two 120v devices in series, one connected to line 1, the other on line 2 and the neutral connections simply connected together. Total load voltage is 240v.
But appliances that use a lot of current like clothes dryers, air conditioners/heat pumps, water heaters, and ovens, can be connected to 240v directly.
It creates some interesting opportunities and challenges.