Now I know from personal experience that not every American out there is going to know exactly what "the mains" is. If the context doesn't make it immediately clear, that's what we Brits call power outlets. I'd considered changing the line when I was lettering the page but decided against it.
The interview I did with Adam Croft for his radio show last week went well and I'll get an MP3 of it up on the site soonly for those of you who missed it.