Not applicable. This is a device accessory, not a topical product.
Contains 1 Ultra Coarse roller head.
Source: Scholl product information.

Remove the used roller head from the device and fit the replacement until it clicks into place. Use light pressure and keep the device moving. Clean after each use. Replace about every three months.

The coarsest roller head in the Scholl range
For thick, established hard skin
Fits all versions of the Scholl electronic foot file
Can be used wet or dry
Replace every three months for performance and hygiene

For use with Scholl electronic foot files only. This is the coarsest head in the range - use light pressure and do not over-file. Keep out of reach of children. For external use on feet. Not for use on broken, cracked or irritated skin, or over open wounds, moles or warts. If you have diabetes, poor circulation or reduced sensation in your feet, do not use without first speaking to your doctor or podiatrist.