Files for difficult calluses contain diamond crystals.
Replacement Files for the Velvet Smooth elechronic file. Two units.
The file must be replaced when it begins to lose its effectiveness. Make sure the device is turned off. remove the file by pressing the button on the outside of the device, pulling it carefully. Insert the new file first on one side and then on the other side, pressing gently. Make sure the file is properly placed before using the device again.