Strings (tennis) be more durable than many other types of strings due to its outstanding tension retention. This may help to offset the high initial cost. The use of a dense string pattern also generally improves the longevity of natural gut. Natural gut is produced by drying fibers extracted from a part of the cow intestine called the serous membrane, or serosa, which contains collagen designed to withstand the stretching and contraction of the intestine. It is this elasticity that makes the fibers useful for tennis string. Sheep intestines have also been used for racquet strings in the past. The first natural
Setar Setar The Setar (, from ', meaning "three" and ', meaning "string") is an Iranian musical instrument. It is a member of the lute family, which is played with the index finger of the right hand. Two and a half centuries ago, a fourth string was added to the Setar which most of the time has the same tone of the bass string. It has 25–27 moveable frets which are usually made of animal intestines or silk. Setar covers about 2 and a half scale (depending on the length the handle). some musicians even use its different strings like chords