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
Strings (tennis) stringing may be a good alternative to natural gut and multi-filament strings. This is especially true for those who have had tennis elbow and find natural gut string to be too costly. Metal wire, usually piano wire, was used in some historical racquets. The "gauge" number determines the thickness of the string. A string rated with a high gauge number is a thinner string, and vice versa. Thinner strings typically offer higher performance but break more frequently than thicker strings. Virtually all modern raquets are strung in a criss-cross horizontal-vertical pattern. Various other patterns have been used in history with