We'll admit it -- we got a little giddy when we saw 5 Seconds of Summer walking the 2014 Billboard Music Awards red carpet. It may be a major U.S. appearance for the boys, but they looked totally at ease working it for the cameras.

The guys stuck to their rocker style, looking coordinated but not too matching, in jeans, T-shirts and flannel. From their perfectly coifed hair to their skinny jeans, these guys are performance-ready. (And we can't wait to see them rock out!)

Check out all of the members of 5 Seconds of Summer in the pics below!

All of the guys look casual, yet polished. We love it!

Frazer Harrison, Getty Images

It's official: Ash can work a hat with the best of 'em!

Frazer Harrison, Getty Images

Check out Calum's smolder! Yep, our hearts just melted a little.

Frazer Harrison, Getty Images

We're totally digging Mikey's hair!

Frazer Harrison, Getty Images

Loving the leather and plaid combo, Luke! It's a total '90s throwback and he makes it work.

Frazer Harrison, Getty Images