Stages Cycling makes Campagnolo crank arm power meters for Campy Record 12-Speed and Campy Super Record 12-Speed. Stages Super Record 12-speed power meters should only be used with Super Record 12-speeds cranks. This is because the threading for Super Record cranks is reverse threaded.
The Stages Record 12-speed power meters however have normal threading. So they will match up with Record 12-speed cranksets as well as with Chorus 12-speed cranksets.
Please note, these power meters attach a sensor to the inside of the left crank arm. On some bikes, there is not enough room between the left crank arm and the chainstay for the sensor to clear the frame. Therefore, you should make sure you have at least 10 mm of clearance. Also, please make sure that you don’t have a bottom bracket mounted rear brake (used on some aero and TT bikes). Please refer to the image below.