Ethicon Precision Cosmetic Conventional Cutting Prime Suture, Size 6-0, 18", Black Monofilament, Needle PC-1, 3/8 Circle A nonabsorbable, sterile, surgical, monofilament suture composed of the long-chain, aliphatic polymers Nylon 6 and Nylon 6.6. ETHILON suture is dyed black or green to enhance visibility in tissue. It is also available undyed (clear).