[Source] The BiVVol RVR-325 (Bith vehicle voice lock) device was a computer module and locking system tied into a vehicle's main control computer and cross-linked to the main drive control package. A hand-held voice recognition link was used to program a series of syllables into the deterrent control program. It was difficult to forge this code. A failed attempt to fool a BiVVoL resulted in a computer lock-out until proof of the owner was established through a second identification system.