Police radio dispatch. Middle aged man says, "Ten four."
Police radio dispatch via interior car perspective. Middle aged woman says, "10 4"
Morse code with a weak signal, number four
MF style telephone button beep via speaker number four.
Antique rotary telephone, dials number four fast, payphone
MF style telephone button beep number four.
Medium group of men shout, "Four"
Computer voice from a Boeing 757 cockpit saying 'serial number one, five, four'
Brushing four four electronic percussive loop sequence