Strap for Divers Sixty-Five 40 Stainless Steel / Bronze / Black / Nato

The lug width of the Oris Divers 65 ref. 01 733 7707 4354-07 5 20 30 is 20 millimetres. This technical specification determines strap compatibility: any strap for this model must have a maximum width of 20mm to fit perfectly between the lugs without friction against the case. Measurement must be taken at the centre of the lug, from shoulder to shoulder of the internal spring bar hole.

The ideal strap depends on intended use: for daily wear, vegetable-tanned alligator in chocolate brown or cognac develops a patina parallel to the natural bronze aging of the case. For intensive diving, a fluoroelastomer (EPDM) rubber strap offers absolute water-resistance and temperature resistance. A ballistic nylon NATO strap represents a versatile compromise. Casati Milano recommends owning at least two straps: one leather and one rubber or NATO.

Strap change requires a specific tool: a spring bar tool. Locate the small hole on the inner shoulder of the lug, insert the rounded tip of the tool into the hole, apply gentle downward pressure to compress the internal spring, and the pin will slide out. Repeat for the opposite lug. The reverse procedure installs the new strap: insert the pin into the new strap, then guide it toward the case lug and allow the spring to expand into position.

Yes, provided the strap has a 20-millimetre lug width and maximum thickness of 20mm to prevent friction against the case. Quality artisanal straps deliver superior performance over OEM straps: vegetable-tanned leather develops natural patina, creating unique personalisation. MilanoStraps supplies 20mm straps specialised for this model, customisable in material, colour and thickness.

Longevity depends on tanning method and usage patterns. An alligator or calf strap with vegetable tanning (natural tannin) subjected to regular saltwater immersion maintains structural integrity for 3–5 years if dried regularly. Freshwater exposure and dry air significantly extend lifespan: in these conditions, 5–7 years are common. Natural patination indicates longevity, not deterioration. Casati Milano recommends professional inspection every 18 months and application of natural wax-based protective treatment.