No need for batteries, plug it in directly for more convenient use. (Before use, please soak your feet in warm water to soften dead skin cells. This step is very important and should not be omitted.) Adjustable speed - You can easily adjust all speeds, fast or slow, and enjoy the fun of foot care. (Pay attention to the strength when using and move back and forth to remove dead skin cells. At the same time, it can also protect healthy skin.) Detachable sandpaper - comes with adhesive backing for easy attachment and removal. Each sandpaper is for one person to use only, making it safer and an ideal choice for nail salons. Three hundred and sixty degrees rotates to easily remove dry cracks, dead skin and calluses on the heel. Trendy appearance - aluminum alloy shell, exquisitely polished, like a compact flashlight, convenient for you to carry with you when traveling or on vacation. Product name: FCM-01 First generation foot grinder Power supply method: plug-in type Voltage: 12V Rated speed: 800 rpm Specification: Black Gross weight: 390g Product size: 12 * 4.4 cm The set includes: 1. Electric foot grinder 2. 60 pieces of frosted paper 3. Power cable 4. Anti-collision inner support 5. Exquisite box 6. Instruction manual