[Speed Adjustable] With speed controller, you can easily adjust various speed, fast or slow is up to you. PLEASE NOTE: The speed range of this foot file is 0-500 rpm, in order to protect our feet, the speed of this machine is not fast, so it will not hurt our feet.[Not Battery Operated] This electronic foot file is not powered by battery, no need to worry low battery again, if you want to use it, just plug it into the socket and you can operate it immediately.[Replaceable Sandpaper Disk] Self adhesive refill pads, you can paste on machine well, won\'t fall off when works. After using, change a new sandpaper disk for another people, one people one disk, sanitary and healthy.[Alloy Body] Nice polished craft, durable and looks more elegant, perfect gift selection.[Package List] 1xgold elelctric foot file, 1xbox repacement sandpaper disk(60pcs), 1xUS plug, 1xuser manual