Catgut suture treatment produces roughly twice the stitch-holding time of plain catgut, but greater tissue inflammation occurs. Full tensile strength is extended to 18–21 days. It is brown rather than straw-colored, and has improved smoothness due to the dry presentation of the thread (plain catgut is wet). It is otherwise similar to plain catgut. Fast catgut suture is heat-treated to give even more rapid absorption in the body. The first known absorbable sutures were made of the intestines of sheep. The manufacturing process was similar to that of natural musical strings for violins and guitar, and also of natural strings for tennis
Tennis rackets have changed over time, as material and engineering advances have been made. For example, the maximum length of the frame had been until 1997, when it was shortened to . Many companies manufacture and distribute tennis rackets. Wilson, Head and Babolat are some of the more commonly used brands; however, many more companies exist. The same companies sponsor players to use these rackets in the hopes that the company name will become more well known by the public. Tennis balls were originally made of cloth strips stitched together with thread and stuffed with feathers. Modern tennis balls are made