This does just what it's supposed to do. I'm not one of the lucky folks whose dog took to this right away, but with some time and effort my pup is coming around. I'm seeing a lot of reviews where this got returned because the dog involved hated the sound. Mine did too at first, but she's starting to love it.If your dog is nervous about nail trims, this likely isn't going to be a cure-all, but it is clearly way more comfortable for my dog than using clippers, and I'm not worried about quicking her black nails. I built up a positive association with the dremel by breaking the process into steps:-dog enjoys the sound of the dremel-dog accepts touching the base of the dremel to her shoulder while it's on (not the rotating part!)-dog accepts me holding her paw with dremel off-dog accepts me massaging her paw and focusing on her nail with dremel off-dog lets me hold her paw with dremel on-dog lets me focus on nail with dremel on-dog lets me touch spinning dremel to her nail for a microsecond-dog lets me slowly build up time spent on each nailFor each step, I used lots of treats and at first gave her a treat every time I did the action. As she got comfortable, I'd take things to the next level a time or two, give her plenty of rewards, then mix it up with some of the easier levels. If she struggles or pulls away, I let her go, but she knows where the treats are and she always comes right back. She's still not totally comfortable with me handling her paws, but she wags her tail when I get the dremel out. I only do one paw per session, with lots of breaks. I make a "click" sound with my tongue when she does the thing I want (I use a clicker for a lot of training but managing dog paw + dremel + treats+ clicker is obviously a bit much). Even if your dog is terrified of the dremel at first, they will likely come round if you put some time in.Maintaining your dog's nails is really important for their posture and joint health. If you're having trouble getting your dog used to this or understanding what you're supposed to do, there are a lot of resources out there. I can't post links here, but the Nail Maintenance for Dogs Facebook group would be a good place to start.