Made by a certified U.S government contractor. 550 LB test  - 7 strand core. Diameter: 5/32". Made in USA. 100% nylon fibers (inside and out). Diameter is 3mm (+/- 0.15mm). Mildew and rot resistent. Certified break strength of 550 pounds. High UV/fade resistent Low shrink and stretch factor. 7 strand internal core (tight inner twist increases strength). Extra tight weave of outer sheath (reduces snags and increases strength). All Military color of C-550 meet US government issue GSA commercial qualifications used worldwide by craftmakers, military personnel, outdoorsman and manufacturers