Only can see the 1st pic, but that does not look like the 4000x.
The USA-4000x was only designed for competitive burps in the lanes and not for daily bumping. It was also the only "4000 watt" amp in their line-up that used that heatsink.
If that happens to be a DE-1000 or a USA 2000/2000x, it is a nice quality amp that will sound great in a daily application as long as the electrical can supply it properly. Don't think it's long enough to be a 2000 or 2000x, and since the 4000x was several inches shorter, I'm sticking with that possibly being a 4000x.