Strap for HydroConquest 39 Automatic Stainless Steel / Blue / Bracelet

The lug width of the Longines HydroConquest L3.780.4.96.6 is 19mm. This measurement is determined by the distance between the two spring bar pins located on the case lugs. Precise measurement is essential to ensure proper strap fit without mechanical stress on the closing mechanism.

The choice depends on intended use. For sport-formal elegance, natural alligator with pronounced grain offers patina and durability. For daily comfort, Hermès-quality calf leather is soft and versatile. For genuine diving capability, high-tenacity nylon NATO or FKM rubber provide absolute water resistance and security. All materials are available in 19mm measure on milanostraps.it.

The procedure requires a specific tool called a spring bar tool to compress the bayonet spring at both lateral case pins. Position the tool in the small groove, gently push to release the spring, extract the pin, remove the old strap, and insert the new one by reversing the process. To avoid case damage, professional replacement is recommended.

Yes. Any strap with 19mm lug width is compatible with this model. milanostraps.it offers a collection of handcrafted straps in 19mm, customizable in leather, colour, length, and construction details. Each strap is manufactured to elevated quality standards and shipped ready to wear.

Leather strap durability depends on material and daily wear. Natural alligator or shell cordovan resists approximately 4–6 years of regular use with proper maintenance. Standard calf leather lasts 2–3 years. Exposure to moisture, salt water, and prolonged sunlight accelerates ageing. The Casati Milano atelier provides an 18-month warranty on all custom straps and offers preservation advice to maximise longevity.