Fish scale the surface, interacting only with the riblet tips, not causing any high-veloctiy flow in the valleys. Since this high velocity flow now only interacts with the riblet-tip, which is a very small surface area, the momentum transfer which causes drag is now much lower than before, thereby effectively reducing drag. Also, this reduces the cross-stream velocity fluctuations, which aids in momentum transfer too. The rough, sandpaper-like texture of shark and ray skin, coupled with its toughness, has led it to be valued as a source of rawhide leather, called shagreen. One of the many historical applications of shark shagreen was
Bonded leather percentage of leather or other fiber content. The guidelines also state that these disclosures should be included in any product advertising that might otherwise mislead consumers as to the composition of the product." Bonded leather Bonded leather, also called reconstituted leather or blended leather, is a term used for a manufactured upholstery material which contains animal hide. It is made as a layered structure of a fiber or paper backer covered with a layer of shredded leather fibers mixed with a polyurethane binder that is embossed with a leather-like texture. It differs from bicast leather, which is made from solid