{"query": "3508", "brand": null, "total": 1, "limit": 10, "matches": [{"slug": "iwc-3508", "brand": "IWC", "ref": "3508", "model": "Ingenieur 500,000 A/m", "case_material": "Stainless Steel", "provenance": "extracted_from_auction_comps", "url": "https://mostexpensivewatches.net/reference/iwc-3508", "description": "Produced between 1989 and 1992, the IWC Ingenieur 500,000 A/m reference 3508 represents a technical peak in anti-magnetic watchmaking. Collectors value this reference for its Caliber 35790, which utilized a niobium-zirconium balance hairspring to achieve magnetic resistance far exceeding its name, tested to over 3.7 million A/m without a soft-iron inner cage. The 34mm stainless steel case, designed by Gérald Genta, maintains a slim profile of 8.8mm. Production was limited due to high manufacturing costs and low yields of the specialized hairspring, with approximately 2,700 total units produced across all metals. On the secondary market, stainless steel examples typically range from $6,000 to $10,000 depending on condition and the presence of original papers. A notable production detail is the \"500,000 A/m\" inscription on the case flank, a feature unique to this specific technical iteration of the Ingenieur line.", "score": 199}]}