STALEKS disposable PapMam files in a roll 100 grit

The cartridge is very easy to replace; you only need to remove the cutting clip (the white metal part), open the top cover of the Donut, and insert the new cartridge. After making the change, you only need to pull out the required length of emery strip and cut it with the white clip.

It is the refill roll to put in the DONUT plastic case if you already have it.