STALEKS PapMam disposable files on a roll, 240 grit

The cartridge is replaced very easily; you just 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 tape and cut it with the white clip. It is the refill roll to place in the DONUT plastic case if you already have it.