My first experience hearing about this fine product occurred well over a decade ago.I was at a bar in Alaska talking to a zoologist who studies Grizzly Bears (Ursus Arctos).He said that the use this particular brush to get “material” for DNA sampling.Having seen that movie with Leonardo De’Crapio, I can only assume that the material samples were to identify the residual remains on their claws to notify the next of kin, since stool samples alone would fall considerably short to provide comfort and respect to any of the bereaved.My second encounter with this product was with an auto mechanic whose skin could best be described as “chimney-esque.”Yet his hands were as clean and sparkly as a newborn babes.I purchased this product forthwith.I can say that I have not been disappointed.I’ve went through three of these so far and always come back.They seem to last me a couple of years with regular scrubbing.What makes this product so unique among its competitors is the long single line that really gets under the fingernails.It really, really does the job.I would recommend this not just to mechanics or people who get their hands in grease and grime, but for anyone who has good grooming habits and wants clean fingernails and such.It’s really the best hand scrubbing brush I’ve ever used—mechanics who resemble chimney sweeps and Grizzly Bear claws notwithstanding.