yes, they're usually sold separately, and you can buy one at any auto parts store. generally they incorporate a steel cable with a big loop on one end that won't fit through the grommet (or whatever they call the round holes at the bottom of the cover) and a smaller loop at the other end to which you run through the other hole and affix your lock. the cables are coated in plastic. since the crossfire's painted rocker panels extend well under the car i am hesitant to use the cable because it will rub against the finish. if you get a locking cable consider fabricating something to insulate the rocker panel from the cable.