You MUST HEAR these singing firefighters

Turn your sound on before watching this vid. These guys sound incredible!

From NBC Bay Area:

In the video, Samoa Crew 61, better known as the "singing crew," is seen walking down off the mountain in Shasta-Trinity National Park and signing acapella while other firefighters sang harmony.

Less than a month after this video was posted, this same crew of firefighters performed the Manu Siva Tau while battling Northern California's Gasquet Fire.