Hublot · Classic Fusion

Strap for Classic Fusion 45 Chronograph Titanium / Blue / 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 Hublot

Lug width20 mm

Case diameter45 mm

Reference521.NX.7170.LR

FamilyClassic Fusion

MovementHublot caliber HUB1143 Hours, Minutes, Small Seconds | Date | Chronograph

CaseTitanium, Resin

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 Classic Fusion 521.NX.7170.LR

Selected for the 20 mm lug width · workshop selection

All 20 mm straps →

The Classic Fusion 521.NX.7170.LR, seen from the bench

The Hublot Classic Fusion 521.NX.7170.LR is a 45mm chronograph combining titanium and resin construction, weighing approximately 105 grams. It features the automatic Hublot HUB1143 caliber with 42-hour power reserve, hours, minutes, small seconds at 6 o'clock, date window, and chronograph function. The case measures 45mm diameter with satin finish, brushed lugs, and a sapphire crystal with anti-reflective treatment. The 20mm lug width accommodates standard 1.5mm spring bars for easy strap replacement. Grade 1 titanium construction with a screw-down caseback provides 50-meter water resistance.

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