4 Heads, 4 address, 4 dmx (xlr) cable, terminator (resistor) if you want to.
Scanner 1 - Address (1)
Scanner 2 - Address (17)
Scanner 3 - Address (33)
Scanner 4 - Address (49)
Cable goes in -> out -> in -> out ... dmx controller
You can address the scanners by poking the 3 buttons in front of the light.
And BTW, incase i mess'd up something, its my 1st post. Let me know if i did helped you out.