Apple · Watch Sport

Strap for Watch Sport 42mm

Integrated bracelet: measurements, the most common questions, and the way to a made-to-measure strap.

Integrated bracelet

The Apple Watch Sport MJ3P2LL is designed with a bracelet integrated into the case. For a compatible made-to-measure strap, the Casati Milano atelier builds it on your watch.

Case diameter36 mm
ReferenceMJ3P2LL
FamilyWatch Sport
MovementApple caliber Apple Watch hours, minutes, seconds, world time | date, day, month, perpetual calendar, week indicator, year indicator | Chronograph | moonphase, Sun position / rising time | alarm | Smartwatch
Year2015
CaseCeramic, Aluminium

Spring bar

Swiss Standard universal spring bars

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

The Watch Sport MJ3P2LL, seen from the bench

The Apple Watch Sport was introduced in 2015 as the entry-level version of the Apple smartwatch range. It integrates the Apple Watch caliber with hourly functions, chronograph, perpetual calendar, moon phases and alarm. The case uses lightweight materials with a touchscreen display and wireless connectivity.

Frequently asked questions

Can you fit a standard strap on the Apple Watch Sport MJ3P2LL?

No, the bracelet is integrated into the case and the attachment is proprietary Apple — a standard strap won't fit. But I can build you a custom one directly in the studio, modelled on the exact geometry of your case.

How does the custom strap work for the Apple Watch Sport?

We work by appointment only at <a href="/pages/casati-booking">Casati Milano</a>. I take measurements directly from your case during the visit, ensuring a perfect fit with the proprietary connectors. Each strap is a unique construction.

Which leather do you recommend for this model?

For the Sport, which was born both sporty and elegant, I choose Tuscan Leather with vegetable tanning. It ages naturally, develops a patina that tells the story of use, and keeps that minimalist lightness that defines this watch's character.

How long does a well-made strap last?

With the right leather and a little care, it lasts for years. Tuscan Leather improves with time, the fibres soften. If you clean it occasionally and let it breathe, it will accompany you without wearing out — leather ages, it doesn't die.

Why does the Apple Watch Sport have such a particular attachment system?

When Apple launched this model in 2015, they chose a proprietary quick-release system to guarantee millimetre precision. It's not a standard — it's a technical architecture that demands real craftsmanship to replicate, and that's why we don't trust this work to anyone outside the studio.

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