Marathon General Purpose Mechanical - References, Prices and Owners' Reviews

Marathon General Purpose Mechanical is a field watch whose exact modern commercial launch year is uncertain, developed by Marathon (Canadian company with Swiss manufacture) in the lineage of U.S. MIL-PRF-46374 and GG-W-113 watches; it targets robust, readable daily use, with fibreshell or steel cases, 12/24 dial, high-contrast hands, and straightforward mechanical calibers that are easy to service.

Field silhouette: 12/24 dial, tritium and readability

The design prioritizes instant legibility: bold Arabic numerals, a clear minute track, high-contrast hands and 12/24 markings so time can be captured at a glance; recent versions pair a flat sapphire crystal with autonomous tritium T25 tubes (sometimes complemented by the brand’s photoluminescent paint) to ensure constant visibility indoors and out, day and night, with no pre-charge.

This “tool-first” approach also shows in the matte, anti-glare surfaces and typography that remain readable from any angle.

Fibreshell/steel cases: size, water resistance and comfort

Two families coexist: the 34 mm high-impact fibreshell GPMs (very light, 16 mm lugs, pressure crown) and the 36 mm parkerized 316L steel “Officer’s” (more wrist presence, same 16 mm lugs, pressure crown); the former emphasizes ultra-light comfort and discretion, the latter adds traditional metal feel and added shock stoutness, with indicative field ratings (≈ 3 ATM for fibreshell, ≈ 5 ATM for steel) suitable for daily splash exposure rather than aquatic use.

Short lugs and DEFSTAN/NATO straps keep the watch planted on the wrist even when you move quickly.

Manual & automatic movements: ETA/Sellita/NH35A

Depending on variant, the GPM uses a Swiss hand-wound (ETA 2801-2 or Sellita SW210-1) on steel models, or a Japanese automatic NH35A on fibreshell models; Marathon opted for proven, easily regulated mechanisms with straightforward upkeep, so the user experience stays consistent: simple, accurate and readable timekeeping with practical autonomy for daily wear or rotation.

Whichever the drive, the goal is reliable, low-maintenance time that suits real-world field constraints.

Chronological milestones and key models (2018–2025)

(2018) Marathon General Purpose Mechanical Officer’s Steel NGM:

Steel reissue rooted in the historic specifications, 36 mm parkerized case, sapphire, 12/24 dial and “No Government Markings” for discreet civilian wear; a Swiss hand-wound caliber, 5 ATM rating and DEFSTAN-style strap deliver a simple, mission-ready package for urban or field use. The overall experience is that of a classic “steel” feel with autonomous night visibility via T25 tubes and maintenance kept to essentials compared to non-useful complications. Marathon General Purpose Mechanical WW194003SS-NGM.

(2019) Marathon General Purpose Mechanical Officer’s Steel US Gov:

36 mm steel variant with “US Government” dial text, again hand-wound, with sapphire crystal, matte dial and tritium markers; the pressure crown and solid back keep the watch sober, MIL-PRF-46374 compliant, and aimed at users who want military purpose without decorative excess. Perceived quality benefits from the parkerized finish and rigid head, well balanced on easy-swap 16 mm straps. Marathon General Purpose Mechanical WW194003SS-0101.

(2020) Marathon General Purpose Mechanical Black 34 mm Standard Issue:

Arrival of the 34 mm fibreshell GPMs: ultra-light composite cases, sapphire, T25 tubes and a dual-winding automatic movement; designed for heavy outdoor use, they combine thermal comfort, scratch protection from sapphire and constant visibility while preserving the “tool” spirit with non-glossy graphics. The 3 ATM rating targets rain and splashes rather than swimming, which suits most field and daily scenarios. Marathon General Purpose Mechanical WW194003BK-0101.

(2021) Marathon General Purpose Mechanical Sage Green 34 mm US Gov:

Fibreshell execution in “sage” with “US Government” text, 34 mm, sapphire, automatic caliber and T25 luminous tubes; the signature 12/24 layout remains, with a more “camouflage” visual character that pairs naturally with green or black DEFSTAN straps. On-wrist feel is nearly weightless, which is appreciated in missions or prolonged wear during warm weather. Marathon General Purpose Mechanical WW194003SG-0003.

(2021) Marathon General Purpose Mechanical Desert Tan 34 mm NGM:

“Desert Tan” variant without government markings, conceived for bright, dusty environments; the 34 mm fibreshell case shrugs off minor knocks, the sapphire crystal resists scratches and T25 tubes provide steady night reading, all on a ballistic-nylon strap. This execution suits those who value lightness with a colorway less common than black or green. Marathon General Purpose Mechanical WW194003DT-0103.

(2023) Marathon General Purpose Mechanical Black 34 mm NGM:

Black fibreshell “No Government Markings” version for users who prefer an uncluttered dial yet identical functionality; in practice, you get sapphire, T25 tubes, an automatic caliber and 3 ATM, in a 34 mm format that slips under cuffs and virtually disappears thanks to its very low mass. This is a sensible gateway into the GPM universe. Marathon General Purpose Mechanical WW194003BK-NGM.

(2024) Marathon General Purpose Mechanical Officer’s Steel (Incabloc):

Update to the 36 mm Officer’s with Incabloc shock protection noted on its Swiss hand-wind movement, plus sapphire and 5 ATM as before; the matte parkerized finish tames reflections, legibility is unchanged and upkeep remains simple, preserving a reliable, recognizable and durable field instrument. The 36 mm/16 mm proportions suit a wide range of wrists. Marathon General Purpose Mechanical WW194003SS-0101.

(2024) Marathon General Purpose Mechanical Jeep Willys 41 mm (SSGPM):

Jeep Willys-inspired 41 mm interpretation in 316L steel, sapphire, Swiss hand-wound movement and dial typography referencing Jeep; it honors shared “field” heritage while keeping 12/24 readability and autonomous night visibility, now in a contemporary footprint (20 mm lugs). This suits wrists wanting more presence without betraying the utilitarian brief. Marathon General Purpose Mechanical WW194033SS-4001.

Advice: size, materials, water, legibility and straps

Wrist & size: 34 mm fibreshell fits slender wrists or anyone prioritizing discretion and lightness; 36 mm steel adds heft and a more “classic” feel, while 41 mm caters to modern presence, especially if you rotate with larger watches.

Visualize the watch under a cuff and in bright sun: the right size is the one you forget when moving.

Materials: fibreshell insulates from heat/cold and minimizes mass—great for long days or hot weather; parkerized steel yields denser feel and added surface toughness, with the impression of a solid “block” on the wrist.

Choose by priority between invisible comfort and a robust object feel.

Water use: fibreshell GPMs are around 3 ATM (hand-washing, rain, splashes), steel Officer’s around 5 ATM (a touch more margin); neither is intended for swimming or diving, though both tolerate daily water exposure very well.

If water is frequent in your routine, treat the GPM as a “dry-use” watch and pick a dedicated diver for the pool.

Legibility & lume: T25 tritium tubes glow without charging—handy at night or in dark rooms; complementary photolume adds a quick boost when light is available, without compromising legibility at rest.

This pairing delivers constant readability with zero pre-action, perfectly in line with the tool brief.

Straps & compatibility: 16 mm (34/36 mm) or 20 mm (41 mm) in DEFSTAN or ballistic nylon, swapping in seconds; the watch “locks” well on single-pass straps, and a small strap kit (black, green, tan) adapts the visual signature to your setting without owning multiple watches.

Own at least two straps to cover office and outdoor roles with no fuss. Other customers’ opinions are essential.

Conclusion

Marathon General Purpose Mechanical is for anyone wanting a true field watch: readable, easy to maintain, tough and coherent in design—whether the ultra-light 34 mm fibreshell, denser 36 mm Officer’s steel or the more present 41 mm edition; your choice hinges on wrist/size balance, weight tolerance and how often you encounter water.

The “tool” signature stems from the 12/24 layout, sapphire, T25 tubes and matte graphics, backed by proven movements that regulate easily; to finalize, weigh your use-case against real-world feedback and consult Dialicious customer reviews.

(Updated September 2025)