Tennis equipment

The components of a tennis racket include a handle, known as the grip, connected to a neck which joins a roughly elliptical frame that holds a matrix of tightly pulled strings. For the first 100 years of the modern game, rackets were of wood and of standard size, and strings were of animal gut. Laminated wood construction yielded more strength in rackets used through most of the 20th century until first metal and then composites of carbon graphite, ceramics, and lighter metals such as titanium were introduced. These stronger materials enabled the production of oversized rackets that yielded yet more power. Meanwhile technology led to the use of synthetic strings that match the feel of gut yet with added durability. Under modern rules of tennis, the rackets must adhere to the following guidelines;[34] The hitting area, composed of the strings, must be flat and generally uniform. The frame of the hitting area may not be more than 29 inches in length and 12.5 inches in width. The entire rackets must be of a fixed shape, size, weight, and weight distribution. There may not be any energy source built into the rackets. The rackets must not provide any kind of communication, instruction or advice to the player during the match. The rules regarding rackets have changed over time, as material and engineering advances have been made. For example, the maximum length of the frame had been 32 inches until 1997, when it was shortened to 29 inches.[35] Balls A Penn tennis ball. Main article: Tennis ball Tennis balls are of hollow rubber with a felt coating. Traditionally white, the predominant color was gradually changed to Optic Yellow in the latter part of the 20th century to allow for improved visibility. Tennis balls must conform to certain criteria for size, weight, deformation, and bounce criteria to be approved for regulation play. The International Tennis Federation (ITF) defines the official diameter as 65.41-68.58 mm (2.575-2.700 inches). Balls must weigh between 56.0 g and 59.4 g (1.975-2.095 ounces).[36] Miscellaneous Advanced players improve their performance through a number of accoutrements. Vibration dampers may be interlaced in the proximal part of the string array for improved feel. Racket handles may be customized with absorbent or rubber-like materials to improve the players' grip. Players often use sweat bands on their wrists to keep their hands dry as well. Finally, although the game can be played in a variety of shoes, specialized tennis shoes have wide, flat soles for stability and a built-up front structure to avoid excess wear