Usage Tips:[20pcs] - Thick Black × 8, effective and fast to remove thick cuticles, suitable for with hard skin; medium blue × 8, suitable for for neutral and hard skin; fine white × 4, suitable for to daily foot care.[Use with different roughness] - Choose the right roller according to the foot skin condition. You can use a rolling pin. high roughness to quickly remove hard, rough skin, then use a roller to low roughness for fine sanding.Durable for long term use.[Good quality, easy to clean. clean] -The cheapest price, the most parts. Our replacement rollers are twice the hardness. micro-diamond crystal abrasive grains, which can withstand wear and remove dead skin more effectively. Washable materials ensure quick and easy cleaning.[Recommended method of use] - It is recommended to clean the sand head after each use, to replace it with accessories every 10 to 50 minutes. 12 times, not to use more than 2 times per week and to use the same piece for a maximum of 3 seconds. to avoid skin damage.