Jaeger-LeCoultre · Master Ultra Thin

Strap for Master Ultra Thin Perpetual White Gold / Silver / Alligator

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

Lug width

20mm

20 mm straps All Jaeger-LeCoultre

Lug width20 mm

Case diameter39 mm

Reference1303520 (aka: Q1303520)

FamilyMaster Ultra Thin

MovementJaeger-LeCoultre caliber 868/1 Hours, Minutes, Seconds | Date, Day, Month, Year Indicator, Perpetual Calendar | Moonphase

CaseWhite Gold

Spring bar

Swiss Standard universal spring bars

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

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Straps for the Master Ultra Thin 1303520 (aka: Q1303520)

Selected for the 20 mm lug width · workshop selection

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The Master Ultra Thin 1303520 (aka: Q1303520), seen from the bench

The Jaeger-LeCoultre Master Ultra Thin 1303520 (Q1303520) features a perpetual calendar and lunar phase complication powered by the JLC 868/1 caliber. The 39mm white gold case houses a movement calculating month lengths and leap years autonomously, requiring manual adjustment approximately every 100 years. The strap width measures 20mm, a standard dimension ensuring broad compatibility with quality artisanal options while maintaining optimal proportions with the case diameter.

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