deb http://deb.debian.org/debian stable main contrib non-free-firmware non-free
deb http://security.debian.org/debian-security stable-security main contrib non-free-firmware non-free

# stable-updates, previously known as 'volatile'
deb http://deb.debian.org/debian stable-updates main contrib non-free-firmware non-free

# stable-backports, previously on backports.debian.org
deb http://deb.debian.org/debian stable-backports main contrib non-free-firmware non-free