A 46mm automatic chronograph on rubber is a different animal from the same watch on steel, and the Marathon CSAR WW194014SS-0130 proves it. With a black dial and a black 3-piece rubber strap, this Chronograph Search and Rescue watch sheds bracelet weight and becomes a far more comfortable companion for diving, boating and long days outdoors.

The strap is Marathon's 3-piece FKM rubber kit, made in La Chaux-de-Fonds. FKM is a dense, durable rubber that resists salt water, UV and chemicals, and the three-piece construction helps a large case like the CSAR sit balanced on the wrist instead of rolling. It is also easier to cinch down over a wetsuit sleeve or a jacket cuff than a metal bracelet, which makes this the most practical configuration for actually taking a 300-meter chronograph into the water.

Nothing else is compromised. The CSAR keeps its ETA Valjoux 7750 automatic chronograph with day/date at 3, its unidirectional 60-minute bezel, its tritium-lit markers and hands with MaraGlo on the subdials and seconds, and its screw-down crown. It was designed for dives, search and rescue operations and flights, and on rubber it feels ready for all three.

CSAR on Rubber: WW194014SS-0130 Specifications

• Reference: Marathon WW194014SS-0130
• Movement: ETA Valjoux 7750 Swiss automatic chronograph, 25 jewels, about 48h
• Case: 46mm 316L steel, roughly 17.5mm thick, 55mm lug to lug
• Water resistance: 30 ATM / 1,000 feet
• Crystal: sapphire
• Black dial, day/date, 1/100-minute scale
• Tritium and MaraGlo lume
• Black 3-piece FKM rubber strap, 22mm lugs

The full CSAR capability, set up for the water.