Strap for SUB 300T Whitepearl

The lug width of the Doxa SUB 300 840.10.011.23 is 20 mm. This measurement represents the external distance between the two lug pins and is the fundamental parameter for ensuring compatibility with any aftermarket strap. To verify it, use a digital calliper positioned between the two lateral protrusions of the case. Only straps specified for 20 mm will guarantee precise fit and long-term stability.

The choice depends on your usage profile. For sartorial elegance, black alligator or vegetable-tanned calf leather offer authentic patina and superior tactile presence. For operational versatility, canvas NATO with leather backing ensures quick changes and durability. For professional diving or intensive marine environments, vulcanised rubber is the ideal choice—a material immune to moisture, easy to sanitise, with absolute thermal stability. We recommend at least two straps to vary according to context.

Strap replacement is a straightforward operation: position your watch on a stable surface and locate the two lug pins (the lateral protrusions of the case). Use a spring bar tool or a sturdy toothpick. Insert the tool into the lateral hole of the pin, disconnect the internal spring, and remove the pin. Repeat on the second pin. Align the new 20 mm strap with the lug holes and reinsert the pins by rotating them until they lock into position. Ensure the strap is equidistant from both sides of the case.

Yes, provided the lug width is exactly 20 mm. Artisanal straps from specialist suppliers—crafted in alligator, calf, shell cordovan, or technical materials such as NATO and rubber—guarantee superior mechanical and qualitative compatibility compared to generic alternatives. Always verify that the vendor specifies the 20 mm lug width. Incorrectly sized straps will cause lateral play or binding on the lugs.

Durability depends on material and usage. Alligator in vegetable tanning, properly maintained (avoiding prolonged moisture, cleaning periodically), can last 5–10 years whilst maintaining structural integrity. Vegetable-tanned calf leather shows more marked wear, typically 3–7 years with daily use. Chrome-tanned leathers offer lower durability. Vulcanised rubber easily exceeds 10 years if not exposed to intense UV rays. NATO canvas remains robust for 5–8 years. The patina evolving on leather is not degradation: it is authentic character that distinguishes every strap.