Bus bar jumper wires

Jumper wires to connect bus bars… acceptable or not? Or what is the proper method? TIA.

What does the panel label say? That panel is almost brand new.

I have no idea. How are they normally connected or what do panels normally say? Yes it was newer.

Do you have a photo of the panel label?

No. It’s a Siemens.

I do have these, if they help.

It appears like the upper neutral bars are factory installed and someone added EGC bars but instead of screwing them to the enclosure they added them the plastic insulator below the factory neutrals. Definitely not code complaint. If you look at the right side you see two rather large neutral conductors possibly #6 AWG being connected to the system neutral by the small #14 or #12 jumper.