Review on ⚙️ Ultimate Sharpening Solution: DMT FCS5C Diafold Diamond Chain - Unmatched Quality for Precision Results by Kevin Hawkins

This diamond file is designed to give the chain a factory sharpness. I've found that if your chain is dull, start with a metal file or whetstone to reshape the teeth. At this stage the cut is sharp, but the chain should be as sharp as it came from the factory. Then use this DMT diamond file to lightly smudge the edges of the teeth to look like they came from the factory. This is an extra step, but it cuts faster, and if you don't hit anything with the chain, it holds all the way. If you find it's still sharp, a few light strokes with a diamond file will make it as sharp as it was when you started.