Surgical gut suture is an absorbable, sterile surgical suture composed of purified connective tissue (mostly collagen) derived from either the serosal layer of beef (bovine) or the submucosal fibrous layer of sheep (ovine) intestines. Surgical gut sutures are available in plain or chromic. Chromic gut is processed to provide greater resistance to absorption. Surgical gut suture is indicated for use in general soft tissue approximation and/or ligation, including use in ophthalmic procedures, but not for use in cardiovascular and neurological tissues. Look Suture 4/0 Chromic Gut 18/45cm C20 20mm 1/2 Circle 12/bx'