AP 3DA. —  A GOOD CHOICE
This tool pulverized my calluses.  There is nothing but dust left on the implement and beneath my foot.  It works well.  I’ve previously used recharagable and battery operated versions, but I bought this one because I lost the power cord to one, and ordered the other by mistake.  I’m glad I didn’t read these reviews.  They’re silly.  One lists a different model number, one talks about different rollers coming with it.  Mine is identified as the Emjoi 3D micro pedi power device, model AP 3DA patent pending.  Mine is navy blue with a purple roller that appears to be the same as the replacement rollers I bought for my rechargeable unit.  The purple rollers were the tougher of the options available at the time I ordered.  I LIKE THIS UNIT AND RECOMMEND IT.  The only reason I am giving it a 4-star rather than a 5-star rating is because of the marketing of the unit.  For example, in addition to its having a litany of reviews for different products in its company, it’s claim to have multi-movement technology may or may not be true.  I don’t see or feel such flexibility.  Neither do I care.  THIS PRODUCT DOES ALL I WANT IT TO DO.  IT REMOVES MY CALLUSES.  Of course, blades do, too, but, if you pull one across your foot at an angle, blades can cut more deeply than intended.  The rechargeable model was terrific ... so long as it was charged.  Brand new, the battery operated unit works just as well as the corded electric unit, but I don’t expect that to last.  I’m just keeping it because I’m not inclined to go through the motions of returning it.
Rating: 4 stars