What is this blue fuse box for

[BURKE]

Hello,
is there anybody out there whom might know what the blue fuse looking box on top of an BATTERY ON an 2010 chevy aveo??.. It looks like an fuse or breaker and do nOt know what it protects. Can it be replaced also?..

Thanks for your advise whom ever checks in..

Burke

[AndrewButler05]

If you're talking about the blue fuse on top of the positive battery terminal, that's the master 100 AMP fuse for the car.