Rolex Sea‑Dweller 4000 Ref 16600 'LC100' (1997) is a professional dive watch equipped with an automatic Cal. 3135 movement. Good condition with visible signs of wear on the case, bezel, and bracelet; the Oyster stainless steel bracelet is slightly stretched and secures with a folding clasp. Includes original box and papers — toolkit, card folder, hang tag, instructions, translation booklet, and Rolex warranty certificate from the purchase in January 1997 (Germany). Movement performance: +4 seconds per 271° amplitude. Key attributes: Black | Stainless steel | Automatic movement Cal. 3135 (+4 s per 271° amplitude) | Helium escape valve at 9 o'clock | Oyster stainless steel bracelet with folding clasp (slightly stretched) | Date display | Black tritium dial with applied hour markers | Date display | Visible signs of wear on case, bezel and bracelet | Dimensions & fit: Fits wrist sizes up to approx. 19.5 cm | Composition & care: Stainless steel | Wipe with a soft cloth; avoid contact with strong chemicals; have serviced by a certified watchmaker as needed.