The diamond droplet bit is the best tool for exfoliating callus near the corner of the free edge. Also used to exfoliate dead skin that has been pushed up and off of the nail plate. Not to be used on the nail plate. Available in medium grit.
Optimal use at 10,000-18,000 RPM with an Erica’s ATA electric file. RPM will vary depending on technique, e-file and newness of bit.