Lum-Tec Combat B73 | USA Assembled Field Watch with MDV Lume

The Combat B73 is part of Lum-Tec's Combat B series, the field watch line Lum-Tec has kept refining since the first Combat B1 arrived in 2007. Lum-Tec says Combat B watches have been battle tested in real military applications and in environments from deserts to freezing mountaintops, and that they are trusted by pilots, ground soldiers, snipers and mountain climbers. Lum-Tec says the Combat B is comfortable on the wrist, legible and accurate, and that its anti-shock capability is well proven in the field.

The B73 is the plain-steel Swiss quartz Combat B. Its forged, heat-treated 43 mm case is left in uncoated bead-blasted steel, and inside is a Swiss Ronda 515 quartz movement. The matte black dial and diamond-cut hands use grade A Swiss BGW9 Super-Luminova as part of Lum-Tec's MDV® luminous technology. It is rated to 200 meters, comes with black and gray nylon straps, and is limited to 500 pieces.

As an authorized Lum-Tec dealer, The CGA Company sells the B73 new, never pre-owned, with free USA shipping. Two nylon straps come with it, and it is a limited, numbered series of 500 worldwide.

Specifications

• Case width: 43 mm, forged 316L surgical-grade stainless steel, heat treated for hardness
• Finish: Bead blasted, with anti-fingerprint coating
• Thickness: 13.6 mm including the domed sapphire
• Lug to lug: 51.5 mm
• Lug width: 22 mm
• Water resistance: 200 meters
• Movement: Swiss Ronda 515 quartz
• Shock protection: Anti-shock movement mounting system
• Crystal: Curved sapphire with military-grade DLC anti-reflective coating on the inside
• Caseback: Threaded 316L stainless steel
• Crown: Threaded, double Viton® seals
• Gaskets: Viton®
• Dial: Matte black with grade A BGW9 Super-Luminova
• Hands: Diamond-cut, filled with A-grade BGW9 Super-Luminova
• Lume: MDV® luminous technology on dial and hands
• Straps included: 2 heavy-grade nylon military straps (one black, one gray) with black PVD hardware
• Warranty: 2-year limited warranty
• Edition: Limited and numbered, 500 pieces worldwide
• Assembly: Designed, assembled by hand and fully tested in Mentor, Ohio

Construction

The B73 case is forged from 316L steel and heat treated. Lum-Tec says forging adds about 37% fatigue strength over a cast case and removes voids and porosity from the metal. Lum-Tec says the bead-blast finish creates a micro work-hardened surface that improves scratch and ding resistance by 8-10%, and an anti-fingerprint layer keeps it clean.

The slightly domed sapphire is Hytrel mounted, with AR coating on the inside. The threaded crown and caseback use silicone-lubricated double Viton® seals, which Lum-Tec says are tested to 30% beyond the 200 m rating. An anti-shock mount helps the movement absorb impacts from drops and knocks.

Heat treatment does two jobs on this case: it keeps the steel stable while it is being forged and hardens the surface once finishing is done. The glare-cutting layer on the inside of the sapphire is a military-grade DLC anti-reflective coating. The case seals are there to stand up to salt water, chemicals and very hot or very cold conditions, not just water pressure, and if the watch is dropped on a hard floor or knocked against a wall, the anti-shock mount lets the movement absorb the hit.

Fit and Straps

The downturned lugs let the 51.5 mm lug-to-lug wrap the wrist, and Lum-Tec says it wears like roughly 46-47 mm. It comes with a black and a gray heavy nylon strap, both with black PVD hardware. Each strap passes under both spring bars for security and is easy to resize.

Lum-Tec says its nylon straps are more durable than typical straps of this type and are designed for easy adjustment, a secure fit and minimal weight on the wrist.

MDV® Lume

The matte black dial is printed with grade A BGW9 Super-Luminova in more than 30 layers over a reflective base, and the diamond-cut hands are filled with the same BGW9. Lum-Tec says RcTritec in Switzerland verified its dials as top Super-Luminova performers.

Lifetime Service

For as long as you own the B73, Lum-Tec provides free battery replacement, seal cleaning and pressure testing in Ohio. Lum-Tec says it regularly sees its watches come back for service after 15 or more years of use, and it puts what it learns from them into new designs. Lifetime services are provided by Lum-Tec under Lum-Tec's terms, not by The CGA Company; for service, contact service@lum-tec.com.

Hand Assembled and Tested in Mentor, Ohio

Lum-Tec says its watches are designed and engineered in Ohio from the ground up, and every Combat B73 is hand assembled and individually tested in Mentor, Ohio, using international and domestic components; the movement in this model is the Swiss Ronda 515 quartz. Lum-Tec says that since 2007 it has produced watches for more than 100 brands around the world, the U.S. government and SWAT teams.

Frequently Asked Questions

What movement does the B73 use?
A Swiss Ronda 515 quartz in an anti-shock mount.

Is the case coated?
No. The B73 is bead-blasted 316L steel with an anti-fingerprint layer. For a black-coated case, see the B71.

What lume does it use?
MDV® luminous technology with grade A BGW9 Super-Luminova on the dial and hands.

Will it fit a smaller wrist?
Usually, yes. The lugs curve down steeply, so the 51.5 mm lug-to-lug wears like roughly 46-47 mm, according to Lum-Tec.

Where is the Combat B73 assembled?
Lum-Tec hand assembles and tests every Combat B73 in Mentor, Ohio, using international and domestic components. The movement is the Swiss Ronda 515 quartz.