Strap for Conquest 34 Stainless Steel - Diamond / MOP - Diamond / Rubber

The lug width of the Longines Conquest L3.430.0.87.9 is 17 millimetres. This dimension is measured orthogonally between the upper and lower points of the case lug. It is critical to respect this measurement to avoid mechanical play: a wider or narrower strap will not fit correctly. The precision of 17mm is a specific characteristic of this model.

For the Conquest L3.430.0.87.9, we recommend a dark brown alligator strap (chocolate or tobacco tone) that elegantly balances the polished stainless steel with the blue dial. Alternatively, burgundy shell cordovan develops an extraordinary patina over time. For those preferring vegetable-tanned leather, a navy or warm brown aniline calf offers tactile softness and personal patina development. A ballistic nylon NATO textile strap is ideal for sporting environments without compromising the case's elegance.

To change the strap, use a spring bar removal tool to extract the horizontal spring bar shaft positioned in the lug. Push gently from inside to outside. Once the bar is removed, the old strap detaches easily. Insert the new strap by aligning the vertical holes and reinsert the bar until it clicks into place. If the strap features a deployante (folding clasp), ensure it is correctly installed on the lug. Never force: the system must slide smoothly into position.

Compatibility depends on brand and model. The 17mm lug width is rare: most watches use 18mm, 16mm, or 20mm. A 17mm strap is specific to the Conquest L3.430.0.87.9 and other Longines models (such as certain Hydroconquest variants) that share the same case geometry. We advise against forcing different sizes: the mechanical safety of the lug depends on precision. Consult your watch manual or measure the lug with a digital calliper.

The durability of a leather strap varies according to material and usage. Quality vegetable-tanned alligator lasts 4–6 years in daily wear. Shell cordovan, due to its density, can exceed 7–8 years. Aniline calf, being softer and more receptive to external agents, lasts 3–5 years. Exposure to water, perspiration, and sunlight accelerates ageing. Casati Milano straps include an 18-month warranty and assistance for early replacements. Regular maintenance (gentle cleaning, drying, conditioning every 6 months) extends useful life.