Doxa
SUB 300 840.10.011.10— lug 20mm
Doxa SUB 300 840.10.011.10: 20mm strap. Alligator, box calf, shell cordovan and rubber, cut and stitched in Milano. Choose your leather.
Artisanal Note
"This model requires a precise 20mm lug width to preserve the original sartorial balance."
Technical Specifications
Doxa 840.10.011.10The essential strap measurement.
Browse 20mm straps →840.10.011.10
ETA caliber 2824-2 Hours, Minutes, Seconds | Date
The Heritage
Compatible Straps
Selected for the 20mm lug width of the SUB 300
FAQ
What is the lug width of the Doxa SUB 300 840.10.011.10?
The lug width of the Doxa SUB 300 840.10.011.10 is 20mm. This width is specific to the 42.50mm case and is non-negotiable: a strap of different dimensions will not fit correctly into the soldered lugs. It is essential to verify this measurement before purchasing any aftermarket strap.
What is the best strap for the Doxa SUB 300 840.10.011.10?
The choice depends on your intended use. For daily elegance: an alligator or vegetable-tanned calf leather in dark brown or black. For underwater functionality: a black FKM rubber, resistant to chlorine and salt water. For historical authenticity: a navy blue fabric NATO. All must have a 20mm lug width to ensure perfect fit.
How do you change the strap on a Doxa SUB 300?
The strap is removed by extracting the spring bars (pins) from the lugs using a dedicated spring bar tool. The pins should be gently pulled downward: pushing horizontally will damage the internal spring. Once the lugs are free, the new 20mm strap is threaded through and the pins are reinserted until they click. We recommend having a professional watchmaker perform this operation to avoid scratches.
What is the compatibility of a 20mm aftermarket strap for the Doxa SUB 300?
Any strap with a 20mm lug width is compatible with the 840.10.011.10. However, we recommend verifying leather thickness (maximum 4mm) and initial stiffness, especially with vegetable tanning. Atelier Casati Milano manually tests each pairing to exclude fit defects or conformity issues.
What is the lifespan of a leather strap for the Doxa SUB 300?
A quality vegetable-tanned calf leather strap lasts approximately 3-5 years with daily use, developing natural patina. Industrial-grade FKM rubber resists for 5-7 years before hardening. A fabric NATO lasts indefinitely, though it may felt over time. Regular maintenance (wax conditioning, post-immersion drying) significantly extends lifespan.