3 DIFFERENT ROLLER HEADS It comes with 3 sanding heads (fine, medium and rough) and a cleaning brush. Use the coarse grinding head is very effective for calluses, the medium grinding head can remove rough dead skin, the use of fine grinding head for daily care. .2 SPEED IN ONE BUTTON electric file: 1700x/min low speed and 2000x/min high speed. The slow speed is suitable for calluses on hands and more delicate rough foot skin care. The high speed is suitable for hard calluses and dead skin. You are free to choose the speed you need.5 LEVELS OF BATTERY DISPLAY You can see how much battery is left and when to charge. 1200mAh Large battery capacity for , can be used for 120 minutes when the device is fully charged. Say goodbye to AA batteries.WATERPROOF DESIGN IPX7 The device is waterproof allowing use in the shower or easy cleaning and a small brush is present to clean the rollers. Do not immerse the charging cable in the water. water or other liquids, and do not rinse it under the tap. Spare the portable part of the power cord before washing the portable part in water. .GENTLE REMOVAL Callus Remover It can gently and effectively peel off hard and aged skin from heels. It is safer and more effective than traditional scrapers. Ergonomically designed, the profile body ensures a comfortable grip. .