If you crossed the Indigo Girls with Joanna Newsom and then made them Swedish, you might end up with something like First Aid Kit. The 'Swedish' element isn't merely a detail - for whatever reason, a lot of pop (or, in this case, folk) singers coming out of the country seem to share a certain timbre and enunciation (and, of course, accent) - but the main musical style from which they draw is squarely American, namely the folk/mountain tradition that still holds such fascination for our (or at least my) modern ears, and they do it well, too.