Nivada Grenchen Chronomaster Aviator Sea Diver vintage chronograph Offered for sale is a Nivada Grenchen Chronomaster Aviator Sea Diver vintage chronograph in stainless steel, featuring a black dial, rotating black bezel and two-register chronograph layout. The dial includes a tachymeter scale, aged luminous hour markers, broad-arrow chronograph hand and the distinctive red countdown section on the subdial at 3 o’clock. The stainless-steel caseback is signed Nivada Grenchen and marked with reference 85004, together with the inscriptions “Chronomaster”, “Stainless Steel”, “Incabloc” and “Waterproof”. Specifications • Brand: Nivada Grenchen • Model: Chronomaster Aviator Sea Diver • Reference: 85004 • Movement: Mechanical manual-winding chronograph • Case material: Stainless steel • Dial: Black • Bezel: Black rotating bezel • Crystal: Acrylic • Strap: Brown leather strap • Period: Approximately 1960s • Case diameter: Approximately 38–39 mm, excluding crown and pushers Condition The watch presents in used vintage condition, with visible wear and marks consistent with its age and use. Swiss manual-winding chronograph, signed Nivada. The movement appears to be based on the renowned Valjoux 23 calibre. The dial and luminous hour markers show natural ageing and patina. The crystal has visible scratches and marks, particularly around the centre. The case, bezel, crown and chronograph pushers also show signs of wear. The service history is unknown. A professional inspection or service may therefore be required before regular use. Included • Watch only • Brown leather strap • No original box • No papers Please study the photographs carefully, as they are an integral part of the description. Sold as is, according to the photographs and description.