Hamilton · Review

Hamilton Khaki Navy Scuba Auto review

By the Watch Winder team · Updated September 2026 · Based on published reviews and owner reports

The Hamilton Khaki Navy Scuba Auto is a dive-style watch for people who mostly don't dive. The 40mm version was refreshed in May 2026 with a wave-textured dial, and it pairs sapphire, a screw-down crown and an 80-hour Swiss automatic for $975. A 43mm version with 300m of water resistance and a ceramic bezel sits above it. Neither is the most original diver around, but both are easy to live with.

Specs at a glance

Design and dial

The Scuba is a classic skin-diver layout: a 60-minute bezel with an inverted triangle at 12, big lumed hands, a red-tipped seconds hand and a date window tucked between 4 and 5. The May 2026 update gave the 40mm a stamped, lacquered wave-pattern dial and applied indices, with wedges at 12, 3, 6 and 9 and dots in between. Those dot markers were previously a 43mm feature. The blue H82425140 has a matching blue bezel; there's also black, a white dial with a blue bezel, and a black dial with a turquoise flange on rubber.

The wave texture gives the dial more depth than the flatter dials it replaces, and the applied markers are a clear step up. Not everyone is convinced: at launch, some readers felt the wavy dials look borrowed from pricier divers. The date is the other sticking point. Reviewers of the previous 40mm pointed out that a white date disc on a dark dial stands out, and the new models keep a white disc.

Lume is Super-LumiNova on the hands and markers. Reviewers rate legibility highly, helped by the long hands and an oversized seconds hand.

Case, size and wearability

Hamilton lists the 40mm case at 40mm by 13mm, with 20mm lugs. It doesn't publish lug to lug, but reviewers measured the 40mm Scuba case at about 50mm. That is a touch long for a 40mm watch, yet reviewers consistently say it hides its size well, and owners with wrists around 6.75 inches report it fits comfortably on bracelet, rubber or leather.

The case is brushed steel with crown guards and a screw-down crown. At 13mm it isn't slim, but it sits well under a cuff for a diver. The 43mm is a different watch on the wrist: about 52mm lug to lug and 22mm lugs, yet slightly thinner at 12.58mm. Reviewers who liked its specification still called it chunky, so try it on if your wrist is under about 7 inches.

Movement and power reserve

Both sizes use the Hamilton H-10, the same calibre found in the Khaki Field Auto. It's Hamilton's version of the Swatch Group's Powermatic 80 platform, which is based on the ETA 2824 architecture but runs at a slower 21,600 vibrations per hour with a longer mainspring to reach 80 hours. The Nivachron balance spring is a titanium-based alloy that resists magnetism far better than a traditional steel spring.

Hamilton doesn't publish a daily accuracy figure for the standard H-10. Reviewers and owners generally report steady timekeeping, and the design is serviced within the Swatch Group network, so plan on a Hamilton service rather than an independent watchmaker.

The reserve is the practical win. Take the Scuba off on Friday evening and it will still be running on Monday morning, which few divers at this price can promise. Check your own schedule with the Will my watch stop? calculator. Watch Winder counts down the H-10's 80-hour reserve and reminds you before the Scuba stops, so you can wear it or wind it in time.

Bracelet and strap

The H82425140 comes on a three-row steel bracelet with a folding clasp, and the rubber-strap versions cost the same $975. Hamilton offering bracelets across most of the 40mm range is new with this update; earlier Scubas leaned heavily on rubber. Reviewers of the earlier rubber versions praised the strap's quality, with a well-shaped buckle and flexible keepers.

The 20mm lug width is the useful part. It opens up almost every NATO, rubber and leather strap on the market, and the Scuba looks at home on all of them. The 43mm moves to 22mm lugs and a push-button folding clasp on its bracelet.

What owners say after months of wear

Long-term feedback on the 40mm Scuba is consistently positive. Owners describe it as the watch that gets worn when nothing else suits the day: comfortable, legible and tough enough for the pool. The 80-hour reserve comes up often, especially from people who rotate between watches and like that the Scuba is usually still running when they come back to it.

The complaints are small and familiar. The bezel is tight and hard to turn without the watch on the wrist. The date window divides opinion. And some owners wish the 40mm had the 43mm's ceramic insert and deeper rating. On the 43mm, the most common reservation is simply its size. Reliability complaints are rare for either version.

Alternatives worth considering

• Tissot Seastar 1000 Powermatic 80: a closely related 80-hour Swatch Group movement with 300m of water resistance, in 40mm and 43mm sizes, for a similar price.
• Seiko Prospex Turtle: a true 200m diver for less money, but a Hardlex crystal and a reserve of about 41 hours.
• Hamilton Khaki Field Auto: same H-10 and 80 hours in a field-watch case, if you don't need a bezel.
• Seiko 5 Sports SRPD: a dive-style daily watch at a third of the price, with a much shorter reserve and a mineral crystal.

Who should buy it

Buy the 40mm Scuba if you want one sporty Swiss automatic for swimming, travel and everyday wear, and you'd rather have an 80-hour movement and a sensible size than a headline dive rating. Choose the 43mm if you really do dive, want ceramic and no date, and have the wrist for 52mm lug to lug. Skip both if you want a design nobody will mistake for anything else.

As part of a rotation, the long reserve makes the Scuba forgiving. Watch Winder suggests which watch to wear next so none of them stop, which also keeps you away from setting the date during the date-change danger zone.

FAQ

Sources

• Hamilton: Khaki Navy Scuba Auto 40mm, H82425140 (specifications and price)
• Hamilton: Khaki Navy Scuba Auto 43mm, H82505140 (specifications and price)
• Monochrome: New Textures and Dial Colours for the Hamilton Khaki Navy Scuba Collection
• aBlogtoWatch: Hamilton Updates & Improves With Khaki Navy Scuba Auto 43mm
• Watch Clicker: Hamilton Khaki Navy Scuba 40mm Review