Scholl Velvet Smooth™ Wet & Dry Roller Heads Ultra Coarse, with diamond crystals (1%, which does not affect coarseness), effectively remove even the toughest hard skin for soft, beautiful feet effortlessly. Made with long-lasting micro-abrasive particles, the Ultra Coarse roller head is great to use on cracked heels and fits all versions of Scholl electronic foot files. It can be used on wet, soaked or dry feet for longer-lasting smoothness. For use in or under water, use only with the Scholl Velvet Smooth Rechargeable Waterproof Foot File. We recommend that you only use Scholl roller heads with Scholl electronic foot files and replace the roller head every 3 months for performance and hygiene. Refer to the packaging of your Scholl Velvet Smooth Electronic Foot File for full usage instructions. Pack Contents 1 roller head. Safety Warning Always read the label and follow the directions for use. If symptoms persist consult your healthcare professional.