Velcro. Coloured scanning electron micrograph (SEM) of two sheets of advanced velcro peeling from each other. Velcro is a material made in two sheets which is used as a reversible fastener on clothing and textiles. It usually consists of a sheet of loops and a complimentary sheets of hooks, but here, the two sheets have interlocking spurs. This arrangement gives a very secure grip, yet one which can still be easily undone. This velcro is designed for fastening cushions and covers to car seats so they don't slip, and for fastening clothing and footwear. Magnification: x20 at 6x7cm size.