Strap for Black Bay 36 S&G / Champagne - Diamond / Bracelet

The lug width of the Tudor Black Bay One 79643-0004 is 19mm. This dimension is standard across vintage Tudor dress models and represents the perfect aesthetic compromise between the 36mm case diameter and visual proportion. When purchasing a strap, always verify that the internal width between the spring bar pins is precisely 19mm: a 20mm strap may force into the case, whilst an undersized strap will create unacceptable play.

For the Black Bay One 79643-0004 we recommend: light brown alligator (cognac), which creates continuity with the black dial; vegetable-tanned calf leather in black or brown, which ages with natural patina; dark grey FKM rubber for daily-wear sports contexts. Not recommended: shell cordovan, which is too rigid for the delicate proportions of the 36mm case, and coloured NATO straps, which diminish the dress formality of the two-tone model.

To change the strap: position the watch dial-down; locate the spring bar pins on either side of the case; using a flat, thin tool (spring bar tool), gently press the pin to compress the internal spring; remove the old strap; insert the new strap (always 19mm width) ensuring that the spring bar pins seat perfectly into the case slots. Avoid excessive pressure on the case, especially the bezel, to prevent scratching the two-tone finish.

Yes, provided the lug width is precisely 19mm. Many aftermarket straps are manufactured in 20mm, 22mm or 24mm; the 79643-0004 accepts no tolerances. MilanoStraps' 19mm-compatible straps are tested for mechanical compatibility. If you prefer a bespoke solution with personally selected leather and custom dimensions, the Casati Milano atelier creates made-to-measure straps with direct fitting, WhatsApp updates and an 18-month warranty.

A quality leather strap (alligator or vegetable-tanned calf) lasts on average 3–5 years with daily wear, varying by climate, humidity exposure and replacement frequency. Alligator, with stable grain, ages more uniformly and can exceed 5 years. Calf, more absorbent, evolves more rapidly but requires minimal maintenance. An FKM rubber strap has similar longevity but is less subject to aesthetic ageing. All MilanoStraps and Casati Milano straps include an 18-month warranty against manufacturing defects.