NET
12 The ten horns that you saw are ten kings who have not yet received a kingdom, but will receive ruling authority as kings with the beast for one hour.
Darby
12 And the ten horns which thou sawest are ten kings, which have not yet received a kingdom, but receive authority as kings one hour with the beast.
KJV
12 And the ten horns which thou sawest are ten kings, which have received no kingdom as yet; but receive power as kings one hour with the beast.