Motorcycle boots are associated with motorcycle riders and range from above ankle to below knee boots. They have an outside of a typical boot but a low heel to control the motorcycle. To improve motorcycle safety, motorcycle boots are generally made from a thick, heavy leather and may include energy absorbing and load spreading padding, metal, plastic and/or composite materials to protect the motorcycle rider's feet, ankles and legs in an accident. For use in wet weather, some boots have a waterproof membrane lining such as Gore-Tex or SympaTex. Depending upon how form-fitting the boot is, to allow a rider to easily get the boot on or off, the shaft may be designed to open lengthwise. If so, Velcro or other hook-and-loop fasteners are typically used on the inner sides of the opening to allow the rider to close the boot over the foot, ankle and leg. This allows for some flexibility for the rider to control the boot's tightness. Some manufacturers also include an internal quick-lacing system between a soft inner leg and the harder outer shell of the boot shaft to further ensure a tight, but comfortable fit. The heel of a racing boot is typically very low: not more than 1/2-inch (13 mm), and sole of the heel and foot is typically rather smooth. A curved plastic or composite plate may be included to cover the shin of the boot to protect the rider's shin. Racing boots Similar to touring boots, racing boots are designed for riding a motorcycle on hard pavement (either the street or a race track) and are usually between 10 and 14 inches in height and made from a combination of leather, metal, plastic and/or man-made composite materials to create a form-fitting, but comfortable boot. The amount of armored protection provided by racing boots is usually greater than touring boots due to the increased potential for injury at the high speeds needed for racing. Typical protection areas are reinforced to protect the shin, instep, ankle (medial and lateral) heel and toes. Often a high-wear pad of metal or composite is attached to the lateral side (outside) of the toe, as this area can contact the ground during extreme cornering. The optimum racing boot has the necessary protection for impact and abrasion while maintaining excellent single-axis flexibility at the ankle between the boot lower and the shaft; for shifting and braking. Styles vary between