Breguet 3700 (Pre-owned - Excellent) — USD 15,600 on eBay

The Patek Philippe Nautilus reference 3700 is recognized as the original iteration of the Nautilus line, introduced in 1976. It established the distinctive porthole-inspired case design and integrated bracelet that would define the collection. Positioned as a luxury sports watch, it represented a significant departure from Patek Philippe's traditional dress watch offerings. This particular example features an 18k yellow gold case measuring 36 mm in diameter, with a fixed bezel and a silver dial. The watch is powered by the self-winding caliber 28-255 C, based on the Jaeger-LeCoultre 920, offering a power reserve of approximately 40 hours. It is fitted with a sapphire crystal and is water-resistant to 30 meters. The Nautilus 3700 holds considerable importance for collectors as the progenitor of the entire Nautilus family. Its design language and mechanical foundation have influenced subsequent generations of the model. Examples in precious metals, such as yellow gold, are particularly sought after for their material rarity within the reference.