Battery Terminal Cleaning Tools
The red tool looks cheaper, but it actually works much better than the all-metal version because its edges stay sharper. Both are designed to reshape damaged lead terminals, but the all-metal one doesn't have enough spring pressure for the post cleaners, and has only 1 cutting edge on each post cleaner.
Since they're rigid, those don't work as well on hard terminals as the plumber's brush style, so use it on steel or copper terminals, or lead terminals with deep pitting.
If these aren't enough, replace the terminals as described in the next several captions.
See also:
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