A set of six files for sharpening the teeth of a saw chain. The diameter is not stated in the name; choose it by the chain pitch and size.
Sharpen the chain when the saw starts to "drift" to one side, the chips become fine, and you have to press hard while cutting. If you are unsure about the diameter, check the chain specifications.
When replacing, clean the seat of dirt, oil and sawdust and inspect the neighboring parts: a worn unit often drags the others with it.
