If “car registration number” is something else, then this is probably worthless. If “car registration number” is similar to the vehicle’s VIN, then this is useful. I think it’s useful for retrieving the stereo’s coding, or its VIN so that it can be put back into the vehicle, but that may be wrong. Is “car registration number” like a vehicle’s license plate number? If that’s the case, then I think this could be useful, but I’ll need to read up on what a license plate number is. If “serial number” is similar to the vehicle’s model serial number (and not the vehicle’s VIN) then this is likely to help, but if you already know the serial number you’re after, you don’t need this. The help text actually doesn’t make it clear what “serial number” is, and it isn’t clear what a “car registration number” is. Here is a smaller version of the help text: It supports radio code retrieval with radio models a.k.a.: Here’s the 2.4 help:ĬRUCC 2.4 – Car Radio Universal Code Calculator, supports . While I don’t doubt the completeness of the tool, I’d have to ask what exactly it’s supposed to do. Crucc 2.4 Car Radio Universal Code Calculator 2.4 17