Tudor · Black Bay One

Strap for Black Bay One 39 Stainless Steel / Black / Bracelet

Takes 21 mm straps. Verified lug width, the straps that fit this model, and answers to the most common questions.

Lug width21 mm
Case diameter39 mm
Reference79660-0001 (aka: M79660-0001)
FamilyBlack Bay One
MovementTudor caliber MT5602 hours, minutes, seconds | chronometer
Year2023
CaseStainless Steel

Spring bar

Spring bars for Tudor

The right category for this model · choose the 21 mm size

Straps for the Black Bay One 79660-0001 (aka: M79660-0001)

Selected for the 21 mm lug width · workshop selection

All 21 mm straps →

The Black Bay One 79660-0001 (aka: M79660-0001), seen from the bench

The Tudor Black Bay One (M79660-0001) is a contemporary reinterpretation of a historic diving instrument featuring a 39mm stainless steel case and a unidirectional bezel. It houses the MT5602 automatic movement, COSC-certified, beating at 4Hz with a 70-hour power reserve and ±2 seconds daily accuracy. Water-resistant to 200 meters, the watch measures 11.3mm thick with a 21mm lug width, offering versatility for aftermarket straps. The satin-finished steel case, sapphire crystal with anti-reflective coating, and Superluminova lume ensure legibility in low-light conditions for professional and recreational diving use.

Frequently asked questions

What is the lug width of the Tudor Black Bay One 79660-0001?

The lug width of the Tudor Black Bay One M79660-0001 is exactly 21mm. This measurement is specific to this model and ensures complete compatibility with all straps produced by Milano Straps in the 21mm category. Always verify the distance between the case lugs (not the width of the mounted strap) to avoid incorrect purchases.

Which strap is most suitable for the Tudor Black Bay One?

For the Black Bay One 79660-0001, we recommend alligator leather in satin or semi-polished finishes, as it naturally complements the brushed case. Vegetable-tanned calf develops an attractive patina over time. If you use the watch for diving, technical FKM rubber is the optimal choice. NATO straps remain a versatile and practical solution for intensive daily wear.

How do you change the strap on the Tudor Black Bay One?

The change is made by removing the spring bars that connect the strap to the case lugs. Use a dedicated tool (spring bar tool) to compress the pin laterally: the strap will detach easily. Align the new strap's holes with the lugs, then reinsert the pin until it clicks into place. The operation takes just minutes and requires no specialised tools. Milano Straps provides photographic details for each strap.

Is it possible to mount an aftermarket strap on the Tudor Black Bay One 79660-0001?

Yes, absolutely. The 21mm lug width is a widely supported standard in the aftermarket strap market. Milano Straps straps in this size are completely compatible with the Black Bay One. Using aftermarket straps does not affect the Tudor warranty and allows you to diversify the watch's aesthetics while maintaining its functional integrity.

How long does a leather strap last on the Tudor Black Bay One?

A quality leather strap (alligator or vegetable-tanned calf) typically lasts 3-5 years with daily use, considering regular maintenance. Factors affecting durability include sun exposure, environmental humidity, cleaning frequency, and use patterns. Vegetable-tanned calf develops a beautiful patina over the years, whilst alligator better maintains its structure. Technical rubber, with proper care, can last 5-7 years.

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