Jaeger-LeCoultre · Master Extreme

Strap for Master Compressor Chronograph Stainless Steel

Takes 20 mm straps. Verified lug width, the straps that fit this model, and answers to the most common questions.

Lug width20 mm
Case diameter42 mm
Reference1758421 (aka: Q1758421)
FamilyMaster Extreme
MovementJaeger-LeCoultre caliber 751F hours, minutes, small seconds | Chronograph, column wheel
Year2015
CaseStainless Steel

Spring bar

Swiss Standard universal spring bars

The right category for this model · 316L steel, all lug widths 13–26 mm

Straps for the Master Extreme 1758421 (aka: Q1758421)

Selected for the 20 mm lug width · workshop selection

All 20 mm straps →

The Master Extreme 1758421 (aka: Q1758421), seen from the bench

The Jaeger-LeCoultre Master Extreme 1758421 (ref. Q1758421) combines sports chronograph functionality with refined elegance in a stainless steel case measuring 41.50mm. Powered by the JLC caliber 751F automatic movement with column wheel mechanism, it features hours, minutes, small seconds, and chronograph functions on a legible dial. The 20mm lug width accommodates Milano Straps' compatible strap collection for this reference.

The next step

The right strap isn't chosen. It is built, together.

From the atelier appointment to delivery, every step is made for those who know that things done well take time. Rare leathers, one piece at a time, eighteen months of warranty.

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Casati Milano · Via XX Settembre 15, Milan · by appointment only