Formato dos Vídeos do YouTube com youtube-dl

youtube-dl --list-formats  https://www.youtube.com/watch?v=xxxxxxxxxxx
[youtube] 3yS_iyJGtQg: Downloading webpage
[youtube] 3yS_iyJGtQg: Extracting video information
[youtube] 3yS_iyJGtQg: Downloading DASH manifest
[info] Available formats for 3yS_iyJGtQg:
format code  extension  resolution note
140          m4a        audio only DASH audio  129k , m4a_dash container, aac  @128k (44100Hz), 7.52MiB
278          webm       256x144    DASH video  104k , webm container, VP9, 13fps, video only, 4.95MiB
17           3gp        176x144
36           3gp        320x240
5            flv        400x240
43           webm       640x360
18           mp4        640x360
22           mp4        1280x720   (best)

youtube-dl -f 5 #Para baixar no formato flv