How we picked
1. A published water-resistance figure, in meters
A dive bezel is styling. A number is a specification. Every pick here states one: 200 m on five of the six, and the sixth — the Steeldive SD1970 — also states 200 m. Where a maker publishes nothing in meters, the watch is not on this page, which is why a couple of otherwise attractive references in our registry are absent. Alongside the figure we have looked for the two features that make a rating mean something day to day: a screw-down or screw-in crown, and a unidirectional bezel. Our guide to the screw-down crown explains why the crown, not the depth number, is the part owners actually get wrong.
2. Crystal, and this is where the money goes
Five of these six state sapphire or domed sapphire; only the Invicta is mineral. That ratio inverts below $200 and it is the single clearest thing this band buys you. It is worth being precise about why: sapphire resists scratching almost completely, which is what keeps a ten-year-old watch looking current, and on a dive watch the crystal is the face of the thing. Our sapphire vs mineral crystal comparison puts a figure on the hardness difference.
3. The measurement nobody publishes
Diameter is the number every listing leads with and the weakest guide to fit. Lug-to-lug — the span from the tip of one lug to the other — is what decides whether a watch overhangs your wrist. Exactly two picks publish it, and the comparison between them is the most useful fact on this page: Orient states 46.5 mm on a 39.9 mm case, and Steeldive states 46.8 mm on a 43.8 mm case. A watch four millimetres wider wears barely longer down the wrist. If you have been buying on diameter, that is the correction.
4. Case material, where it is stated
Titanium is roughly 40% lighter than stainless steel by volume, and at this price you can have it — but only the Watchdives states the grade(Grade 2, the commercially pure specification) rather than just the word. On a dive watch that weight saving matters more than on a dress watch, because the case is thick and the bracelet is heavy. The honest counterweight is hardness: titanium marks more easily than hardened steel, which is why the Watchdives’ internal bezel ring is a sensible choice — there is no exposed bezel edge to scuff. Our titanium roundup covers the material properly.
What $500 does not buy
A named caliber from a major brand. Bulova publishes the most complete specification of any watch on this page — anti-reflective sapphire, WR200, a 41 mm case, a 42-hour reserve, a unidirectional bezel, a crystal case back, a 20 mm lug width and, uniquely in our whole registry, the dial colour in words — and then declines to name the movement. Orient names its caliber; Steeldive and ADDIESDIVE name a Seiko NH35; Watchdives names an SL3001; Invicta names an NH35A on this reference and nothing at all on several others. The brand you have heard of is the one that tells you least.
An accuracy figure. Not one of the six publishes a daily rate for its reference. Orient publishes +25 to -15 seconds a day for its F6S22 elsewhere in the range and Seiko publishes +45/-35 for the 4R36, so the figures exist in this market — just not attached to these watches. Our guide to automatic watch accuracy explains what a normal rate looks like and when a watch is genuinely misbehaving.
ISO 6425 certification. Covered above, and worth repeating because it is the most common misunderstanding in the category. If you intend to scuba dive with a watch rather than swim with it, the marking on the dial is the thing to look for, and it starts above this band.
Which one, for which buyer
A normal wrist and a watch you keep: the Orient AC0Q. Sapphire, a real in-house caliber with hacking and hand-winding, 200 m and a 39.9 mm case with a published lug-to-lug. Note the naming trap: the Amazon title reads “Orient Mako Automatic Green Dial”, but Orient Watch USA’s page for RA-AC0Q11E30B calls it the AC0Q Diver — and the actual Mako is a different case with different published figures. Buy on the reference number.
A big wrist: the Steeldive SD1970, which has its own review here, or the Watchdives at 42 mm. Also see our big-wrist roundup.
Wearing it with a jacket as well as a wetsuit: the Bulova Marine Star 98B466. It is the only pick whose maker describes the dial in words — a sunray finish shifting from bright blue at the centre to black at the edge — and the only one with an H-link bracelet and a published lug width.
Spending the least: the Invicta 8927, and it is a genuinely sound buy rather than a throwaway. Our Invicta roundup records the relevant caveat: nothing in Invicta’s automatic range uses sapphire, and nothing in it carries ISO 6425.
