Strap for Annual Calendar Chronograph 5961

The Patek Philippe Complications 5961P-013 features a lug width of precisely 18mm. This dimension is specific to this reference and is crucial for ensuring correct fit and proportional alignment with the 40.50mm platinum case. A strap with a different lug width will not attach properly to the case's Spring Bars.

Genuine alligator leather in neutral tones—black, dark brown, charcoal grey—represents the ideal choice. Shell cordovan with vegetable tanning offers an excellent alternative for those seeking superior density and longevity. Tuscan calf leather in cognac or hazelnut tones works well for those desiring elegant contrast with the platinum whilst maintaining the aesthetic restraint this timepiece demands.

Strap replacement occurs via Spring Bars—support rods connecting the strap to the case at the lug positions. A dedicated Spring Bar Tool is required to extract the rods from the holes in the case. Once extracted, the old strap is removed and the new one is attached to the same rods. We strongly recommend against DIY attempts on a watch of this calibre; specialist services such as Casati Milano are the appropriate choice.

Yes, it is entirely possible. Many high-quality aftermarket straps respect the 18mm lug width specification precisely and prove compatible with the 5961P-013. The critical decision is not technical compatibility, but aesthetic and material synergy. A bespoke strap in genuine alligator or shell cordovan of exceptional construction elevates the watch's perceived value significantly. Casati Milano offers a specialised collection for this lug width.

A genuine alligator strap with vegetable tanning typically lasts 4-6 years under daily wear. Shell cordovan, due to its dense fibrous structure, can exceed 7-8 years. Longevity depends on climatic exposure (sweat, humidity), frequency of wear, and regular care. A Casati Milano strap is engineered with tolerances permitting refurbishment—replacement of worn components only—extending overall lifespan to 12-15 years. The 18-month warranty covers production defects.