name for this material is catgut. The first natural gut tennis string was rumored to be manufactured in 1875 by Pierre Babolat, who would launch the VS brand of gut fifty years later. Natural gut is usually offered in coated form, to reduce its tendency to unravel, particularly when humid or wet. Even though handles were used after gloves in “Jeu de Paume,” the first prototype of the modern racket used today was created in Italy in 1583. The first rackets were made of wood and had strings made of gut at this time. The rackets had a slightly different shape than are used today; however, they are the first semblance of a racket being used for tennis. The strings utilized in these rackets were similar to strings that had been used in instruments previously. Synthetic gut Synthetic gut is nylon, nearly always composed of a single filament. It is a very inexpensive string to manufacture and is generally the least expensive string to purchase. Small changes from pure nylon are usually found in strings sold as "synthetic gut". Textured coatings, colorants and the addition of a small amount of Kevlar are the most common changes. Some manufacturers, such as Gosen, label nylon strings with words like "sheep", as in sheep intestine, although such strings contain no gut. Synthetic gut, as it is used for mono-filament nylon strings, is now a misnomer, as the creation of multi-filament strings has provided players with a better approximation of natural gut's performance. Modern "synthetic gut" is actually a multi-filament string that holds its tension extremely well and which has a dynamic stiffness profile that is closest to natural gut, although the industry continues to apply the term to mono-filament nylon strings. Multi-filament, or "multi" Multi-filament strings, known commonly as "multis" are strings that have more than one filament. They are most commonly made of many filaments of nylon, but can incorporate other materials such as polyurethane, Zyex, Vectran, Kevlar, and other materials. Multi-filament strings offer better elasticity than single filament strings, but usually inferior durability. No multi-filament string holds its tension as well as natural gut, and none of them is as soft. However, in comparison to mono-filament "synthetic gut", multi-filament strings can offer a much closer approximation of natural gut's performance. The softest multi-filament strings can be made with Zyex and polyolefin, although some of the softest of these strings are no