Lum-Tec Combat B64 Chronograph | USA Assembled Field Watch with MDV Lume

The Combat B64 adds a chronograph to Lum-Tec's Combat B field watch, a line that started with the B1 in 2007 and has been used in military work and harsh climates ever since. It has a gunmetal-coated forged steel case, a matte gray dial with blue-glow lume, and a Japanese quartz chronograph for timing anything up to an hour.

As an authorized Lum-Tec dealer, The CGA Company sells the B64 new, never pre-owned, with free USA shipping. It comes with a leather strap and a nylon strap, 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
• Coating: Military-grade titanium carbide gunmetal PVD hard coating over a bead-blasted finish
• Thickness: 13.6 mm including the domed sapphire
• Lug to lug: 51.5 mm with a curved lug profile
• Lug width: 22 mm
• Water resistance: 200 meters
• Movement: Japanese Miyota OS21J quartz chronograph
• Functions: 60-minute chronograph timer and a 24-hour sub-dial indicator
• Battery life: About 5 years
• Shock protection: Anti-shock movement mounting system
• Crystal: Curved sapphire with military-grade AR coating
• Caseback: Solid, threaded, double-diamond sealed
• Crown: Threaded, double-diamond seals
• Gaskets: Viton®
• Dial: Anti-reflective matte gray
• Lume: MDV® luminous technology, X1-grade Swiss C3 BL (blue glow) in 30 layers
• Hands: Diamond-cut, filled with X1-grade Super-Luminova
• Straps included: Leather military strap plus heavy-grade gray nylon strap, each fitted with gunmetal 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 Combat B case is forged from 316L steel, not cast, and then heat treated. Lum-Tec says forging adds about 37% fatigue strength over a typical cast case, and that the bead-blasted surface resists scratches and dings 8-10% better than brushed or polished steel. On the B64, a gunmetal titanium carbide PVD hard coat covers the steel.

A thick, slightly domed sapphire in a Hytrel mount keeps glare down. Silicone-lubricated double seals protect the threaded crown and the solid threaded caseback. Lum-Tec says its Combat B sealing has improved by more than 200% since the original B1, and it tests it to 30% beyond the 200 m rating.

Fit and Straps

The lugs curve down steeply, so the 51.5 mm lug-to-lug sits closer to the wrist than the number suggests. Lum-Tec says it wears like roughly 46-47 mm. The B64 comes with two 22 mm straps: a leather military strap for everyday wear and a heavy-grade gray nylon strap for harder use. Both have gunmetal PVD hardware.

MDV® Lume

The matte gray dial carries X1-grade Swiss C3 BL Super-Luminova, which glows blue, printed in 30 layers over a reflective base so the light is directed outward. The diamond-cut hands are filled with X1-grade Super-Luminova. Lum-Tec says RcTritec in Switzerland verified its dials as top Super-Luminova performers.

Lifetime Service

For as long as you own the B64, Lum-Tec provides free battery replacement, seal cleaning and pressure testing in Ohio. For service, contact service@lum-tec.com.

Assembled in Mentor, Ohio

Lum-Tec assembles its watches in the USA, in Mentor, Ohio, using international and domestic components, such as this model's Japanese Miyota OS21J chronograph movement. Each B64 is assembled by hand and fully tested there.

Frequently Asked Questions

What does the chronograph do?
The Miyota OS21J quartz movement has a 60-minute chronograph timer and a 24-hour sub-dial indicator.

What color is the lume?
Blue. The dial uses X1-grade Swiss C3 BL Super-Luminova in 30 layers, part of Lum-Tec's MDV® luminous technology.

How long does the battery last, and who replaces it?
Battery life is about 5 years, and Lum-Tec replaces the battery free for life, along with seal cleaning and pressure testing.

Which straps come with it?
Two 22 mm military straps with gunmetal PVD hardware: one leather and one heavy-grade gray nylon.

How water resistant is it?
200 meters, with a threaded crown and a solid, double-diamond-sealed caseback.