This device is claimed to file your animal's nails/claws whilst avoiding the cracking, splintering, damage to the "quick" and anxiety/discomfort/pain which can happen with cutting. The business end is basically a wheel wrapped with emery cloth, the head is covered by a guard/guide and the whole thing is battery-powered. It's bigger than I expected, mainly because it has to accomodate 2 C-cell batteries. You switch it on, introduce the nail/claw through the (transparent) slot in the guard, let the nail/claw gently contact the revolving emery cloth, and that's it. No chance whatsoever of anything going wrong. Does it work? Yes, and it's fairly quiet. Took it straight out of the box and got to work, dog wasn't in the least bit worried, he just watched with interest (but then he's a fairly laid back Border Collie- you may want to tread a bit more carefully if you've got a neurotic German Shepherd....) The guard also collects the removed material, which is basically dust. There's an inbuilt sensor which slows the speed down if you press the nail in too hard, and I was suprised at how many times this cut in- it really is "gently, gently". If you have a big dog with big nails, it will take a few minutes. Originally on sale around £25, these can now be had brand new for under £5, and I reckon that's a bargain. Packs of 12 replacement Emery wraps can be found on E-Bay for around £3. This is an American product, so UK buyers are prewarned that it comes with a MASS of literature suggesting you introduce it to the animal very gradually, preferably with the aid of a canine psychiatrist, and also recommending you wear protective goggles, crash helmet and full NBC suit because of the danger posed by any microscopic particles of dust which may leave the guard/guide.