DemeTech's Plain Catgut suture is an absorbable, sterile, surgical suture composed of highly purified connective tissue (mostly collagen) derived from either beef or sheep intestines. Due to an extremely short absorption period, DemeTech's Plain Catgut elicits only minimal reaction in tissues. The percentage of collagen in the catgut suture often determines the quality of the suture. Higher percentages of collagen allow for: superior tensile strength, longer absorption times, and lower reactions in vivo.