That's a European panel with the front cover missing!
The wiring in and out of the breakers would not normally be exposed like that.
It's definitely not suitable for use in the US though, they're 230V 50Hz European spec components.
Also, has your customer noticed the thousands of miles of "dirty copper" between the power station and his home!?
Or the fact that the breakers in that panel are just fitted with nice gold plated screws, they're the same siemens breakers that handle the circuits for my washing machine
I wouldn't suggest installing it and certainly not with the backs of the breakers exposed like that.
It looks like a home-brew panel!