Swedish sisters Johanna and Klara Soderberg - aka First Aid Kid - are well-known for their beautiful harmonies.
They've covered some famous harmony-led songs in the past to great success - including their version of Fleet Foxes' 'Tiger Mountain Peasant Song', which led to them being 'discovered' on MySpace several years ago.
Now, the duo have taken on Simon & Garfunkel's 'America', which they performed on Late Night with David Letterman at the end of last week.
They originally released the song as a special edition 10-inch vinyl for Record Store Day's 'Black Friday' event last November.
Watch their Letterman performance below: