some tips [SEP] i got this thing when i was working retail a lot of long shifts standing stock still wih only a single minute lunch break can kinda kill your feet especially when you are heavy i got this thing to help me deal with the calluses and just oiverall roughness of my feet by itself it does a great job but even using the black tip if you have feet like mine will not do you much good especially since that low grit means it tends to catch and stop itself due to thesafety feature built in to the deviceso some tips i found are use this once or twice a week it feels like it is made for that especially with the high grit white tip for fine filing and polishinguse with a cheap dust mask and away from electronics trust me while most dust is dead skin as it is this thing does not so much grind away deadskin and calluses as it vaporizes them nothing worse than having to dust a computer or going to check your phone and just realise the horror you have createddo not use pressure the machine does the work for you and applying any pressure especially witha black tip will just flat out stop the machineand lastly and probably the most important never stop moving even if it is a particurally rough spot or calluses even if it is on low if you leave it in the same place too long you will give yourself a friction burn or even worse take of too much and leave your foot raw instead if you want to focus on the same area just rapidly tap the machine aagainst the problem area giving it a second or two to cool off in beteween for the rest of the areas making sweepng brushing or lazy cricular motions work the best