That’s an aftermarket brake booster and master cylinder. Universal GM units that most brake companies sell. Chances are the car was originally a manual brake car. I have the same car with really similar options (with manual disc brakes) but mine is GY3 Curious Yellow. Yours looks good in white!
I had a feeling that was the case. I'd mentioned in an earlier post, tag has L31 as an option, but no longer on car. Looking to replace them. I have a question for you, does your car have the slotted bumper front and rear?