Synthetic or man-made fibres are manufactured, and therefore can be more controlled in terms of the shape, finish, diameter, length and tensile strength than an animal hair. Each animal produces a different hair depending on its diet and environment and weather. This means there is no consistency from one animal to another and from one season or time of year to another. So, fur farmers sometimes mix the hair types all together to get a general level of quality for that hair bundle. Man-made fibres are consistent, so each brush manufactured is made to the very same standards as every other brush of that kind. You wouldn't want to buy a pair of jeans in your size at one store that turned out to be too large, another store was too small, yet another store was blue, and green at another. Even though the brand and make and size of the pants was supposed to be the same. Artis brushes uses a type of fibre that is a man-made monofilament. This is the premium fibre for making cosmetic brushes and is superior to other synthetic fibres like Taklon or Nylon. The Artis® CosmeFibre® resists moisture better, keeps it shape better and resists microbes better than other fibres. And out-performs animal fibres in testing.