Strap for SUB 300T Divingstar / Bracelet

The lug width of the Doxa SUB 300 840.10.361.10 is 20.00 mm. This specific dimension requires dedicated watch straps and is not interchangeable with the more common 22 or 24 mm formats. Always measure your lug width before purchasing: place a calliper between the inner attachments of the case, from one side to the other, to verify the exact width.

The orange Tropical dial of the SUB 300 pairs ideally with warm-toned straps: dark brown or cognac alligator, black calf leather, grey pearl shell cordovan. For professional diving, opt for FKM rubber in dark grey or black, which resists saltwater and chlorine exposure. Avoid bright red or orange straps, which would create discordant contrast with the dial.

Strap replacement requires a spring bar tool (specialized removal device). Locate the metal springs at the ends of the lugs and gently press one spring downward with the tool, then extract the bar from its hole. Repeat on the other side. Insert the bar into the new strap, aligning the holes, then reposition the spring. Verify that both sides are securely fastened. Professional installation is available through MilanoStraps or the Casati Milano atelier.

Yes, any strap with a 20 mm lug width is technically compatible. However, we recommend selecting artisanal straps of high quality, made with noble materials (alligator, vegetable-tanned calf, vulcanised FKM rubber). MilanoStraps offers a curated selection of 20 mm straps that guarantee durability and aesthetic coherence with the toolwatch character of the SUB 300.

Leather strap durability depends on usage and maintenance habits. A high-quality leather with vegetable tanning, subjected to ordinary wear (5–8 hours daily), maintains structural integrity for 3–5 years. Constant humidity exposure shortens this lifespan to 12–24 months. To extend strap life, apply protective balm every six months, avoid prolonged immersion with leather straps, and consider FKM rubber for humid environments. MilanoStraps straps are constructed for longevity: premium leathers and artisanal techniques reduce the risk of premature failure.