Jumbo stainless steel Tri-Compax, cal 287. All original, as far as I can tell. Diameter: 36.5mm. Lug-to-lug: 45mm. Thickness: 12.5mm. Lug width: 19mm. Case appears unpolished, in good condition, with minimal wear marks. The case serial and reference numbers are legible. Currently keeping time and functioning correctly, except that the chrono sweep hand resets to the 58-second mark. Service history unknown; should be serviced. There is discoloration of the original dial, more prominent in indirect sunlight, as I have tried to demonstrate in the photos. Hour numerals are gilt and quite reflective in the right light. Delivered on an unworn vintage JB Champion gray lizard/calf strap. Asking $4000 USD, shipped and insured. Watch and I are in the USA. Thanks ΩF for the space!