Check out this old Square D split bus panel. With the breaker in you cannot tell how bad it is. But with the breakers out see all those marks from overheating? Those are spots that can cause a fire. The panel this came out of had breakers that would not trip when they should have and let the wiring in the walls heat up! If you have an old panel like this, let us know and we can come check it out to make sure it’s safe!