Mystery part numbers on O2 sensors!

[dr-rjp]

Two months ago, I had all three O2 sensors replaced. I asked the mechanic to give me back the O2 sensora that he removed from my car.

Recently, I happen to check the part numbers on them, and I could not find a match for them anywhere.

Here are the numbers for the pre-cat sensor:

Mystery Part# on a BOSCH O2 sensor

BOSCH A24-A71052 7X240

This number is not listed in the Bosch catalog, nor can I find anything on Google for any combination of these numbers that are even remotely related to anything automotive.

Here are the numbers of the post-cat sensor:

12559850DENSO234000-508009B20

I did find a match in the DENSO catalog, but the match was to a Isuzu Rodeo 4x4.

Can anyone find a match for the pre-cat sensor numbers, and find a match for the post-cat sensor numbers to a 4th Gen?

If not, then the mechanic gave me back someone else's O2 sensors.

Thanks.