Strap for Hydroconquest Quartz 41 Blue

The lug width (ansa measurement) of the Longines HydroConquest L3.689.4.03.6 is 20mm. This measurement represents the distance between the inner edges of the lugs attached to the case. To verify it accurately, use a digital caliper positioned perpendicularly between the lugs without applying excessive pressure. On milanostraps.it you will find the complete collection of 20mm straps pre-verified for compatibility.

Your choice depends on intended use: for formal elegance, we recommend vegetable-tanned alligator or burgundy shell cordovan, which create sophisticated contrast with the blue dial. For daily wear, Tuscan calf offers easy maintenance and progressive patina development. If the watch is destined for water (sea, swimming pool), NATO nylon 5-ring straps or FKM rubber resist moisture and chemical agents. Your final decision reflects your personal relationship with the timepiece.

To change the strap, first remove the deployante (if present, by gently unscrewing it) or slide the strap from the lugs. Use a spring bar tool (instrument with two micro-levers) to push the fixing pins inward and release the lug. Proceed one at a time, supporting the case. Insert the new strap aligning the lugs to the holes and secure the pins using the same tool, verifying that the strap is firmly seated. If you have a deployante, consult an expert to reinstall it at the correct size.

Yes, any strap with a 20mm lug width is completely compatible. The craftsmen at milanostraps.it manufacture straps specifically tailored to this width, selecting premium leathers (alligator, calf, shell cordovan) and durable stitching. You can choose from ready-made collections for rapid shipment or request a custom-made model with colour variants, length adjustments and buckle options (standard or deployante) by contacting the Casati Milano atelier.

A premium leather strap (vegetable-tanned or shell cordovan) typically lasts 3–4 years with daily use, provided careful maintenance: always dry it after contact with fresh or salt water, avoid prolonged direct sunlight exposure, and apply vegetable balm every 6–8 months. If the watch is intended for water use, preferably use FKM rubber or synthetic NATO straps, which offer superior durability (5–7 years). Straps from milanostraps.it include an 18-month warranty and buckle replacement and stitching repair services.