Doxa
SUB 300 821.10.201.10— lug 20mm

The lug width of the Doxa SUB 300 821.10.201.10 is 20 mm. This measurement represents the centre distance between the two attachment points on the case where the strap is inserted. It is essential to verify this measurement with precision before ordering an aftermarket strap, as even a 1 mm difference results in mechanical incompatibility.

The Doxa SUB 300 accepts multiple interpretations: for authentic marine use, FKM rubber in hydrophobic grade is the technical choice without compromise; for sober elegance, natural alligator in grey or burgundy tones enhances the orange dial; for noble ageing, vegetable-tanned calf develops caramel patina over time; for urban versatility, NATO in neutral colours (khaki, grey) maintains technical character without theatricality.

The Doxa SUB 300 821.10.201.10 uses standard bayonet spring bars for strap attachment. Obtain a steel strap removal tool: position it perpendicular to the wrist, press lightly against the spring until it releases from the anchor hole, then extract the worn strap. Verify that the attachment holes are free from debris before inserting the new strap. The deployante must be affixed to the new strap before installation on the case.

Yes, the Doxa SUB 300 821.10.201.10 is compatible with any certified 20 mm quality strap, provided the lateral passants (ears) are dimensioned correctly to enter the case manoeuvre spaces without contacting the crystal or caseback. We recommend straps specifically tested for 42–44 mm models to ensure harmonious proportions and mechanical functionality.

Leather strap longevity depends on frequency of use and humidity exposure. On a SUB 300 used occasionally in dry environments, quality calf resists 3–5 years before fibre replacement is required. If regularly exposed to marine humidity, even the finest vegetable alligator tends to lose elasticity within 18–24 months. For frequent marine use, FKM rubber offers indefinite durability with only freshwater rinsing maintenance.