| OrientMako (AA08, gradient dial) | SeikoProspex King Turtle | |
|---|---|---|
| Price (US) | $390 | Not published |
| Reference | RA-AA0810N39B | SRPE03 |
| Movement | Orient F6922, automatic | Seiko 4R36, automatic |
| Power reserve | About 40 hours | About 41 hours |
| Rated accuracy | +25/−15 sec/day (edge) | +45/−35 sec/day |
| Hacking / hand-winding | Yes / Yes | Yes / Yes |
| Jewels | 22 | 24 |
| Beat rate | 21,600 vph | 21,600 vph |
| Case diameter | 41.8mm (edge) | 45mm |
| Thickness | 12.8mm | 13.2mm |
| Lug to lug | 46.8mm | 47.7mm |
| Lug width | 22mm | Not published |
| Crystal | Sapphire | Sapphire with magnifier (cyclops) |
| Caseback | Not published | Solid steel, screw-down, Seiko wave engraving |
| Water resistance | 200m | 200m diver’s (air diving) (edge) |
| Bezel | Unidirectional, 120 clicks, stainless steel bezel | Unidirectional notched steel bezel, 60-minute ceramic insert (edge) |
| Crown | Screw-down | Screw-down, at 4 o’clock |
| Lume | Luminous hands and hour markers | LumiBrite |
| Bracelet / strap | 316L stainless steel bracelet, fold-over clasp with diver’s safety | Stainless steel three-link bracelet, three-fold clasp with secure lock, push-button release and diving extension (edge) |
| Warranty | 3 years (Orient Watch USA) | 3 years (Seiko USA, purchases on or after July 1, 2024) |
Price
The gradient-dial Mako, reference RA-AA0810N39B, is $390 at Orient Watch USA.
The Seiko side is harder to pin down. The King Turtle SRPE03 no longer has a page on Seiko’s US sites, and a search of Seiko USA’s online store turns up only a sibling, the SRPE05, listed at $625 and sold out. We have no verified US price for the SRPE03, so we do not give one.
So this comparison is for buyers who have found a King Turtle at a retailer and want to weigh it against an Orient sold new by its maker. Carry the retailer’s price through the rest of this article, and confirm the seller is an authorized US dealer, since Seiko USA’s warranty depends on it.
Design
Orient’s Mako line dates to 2004, and Orient Watch USA dates the current Mako-3 generation to 2023. This gradient model is an earlier listing, from November 2021, and shares the Mako-3’s case dimensions, sapphire crystal and movement. Orient Watch USA describes the line as having “deep gradient dials, classic diver design, and a rich, modern patina.”
The King Turtle belongs to Seiko’s Prospex range. It arrived in 2020 with a sapphire crystal carrying a magnifier over the day and date, a notched steel bezel with a ceramic 60-minute insert and a black dial with a squared, waffle-like pattern. The crown sits at 4 o’clock.
The King Turtle’s case and textured dial give it the stronger identity. The Orient, with its gradient dial, is the quieter watch.
Movement
The Orient uses the F6922, made in Akita Prefecture by Akita Epson. It has 22 jewels, beats at 21,600 vph and runs for about 40 hours, with hacking, hand-winding and a day-date.
The Seiko uses the 4R36, with 24 jewels, the same 21,600 vph and about 41 hours of reserve, and it also hacks, hand-winds and shows the day and date. Monochrome gives the King Turtle’s reserve as 40 hours, but Seiko’s manual for the caliber says about 41, and we use Seiko’s figure.
These are close equivalents. The difference that matters is the accuracy rating, covered below, and on that basis the Orient takes Best Movement by a narrow margin. Our explainer on Orient’s in-house movements covers the F6922 in more depth.
Case and Dimensions
The Orient measures 41.8mm across, 12.8mm thick and 46.8mm lug to lug, with 22mm lugs and a screw-down crown. Orient does not state its caseback type.
The King Turtle measures 45mm across, 13.2mm thick and 47.7mm lug to lug, according to Monochrome. Its brushed and polished steel case has a screw-down crown at 4 o’clock and a solid screw-down caseback with a Seiko wave engraving. Seiko lists 22mm lugs for the sibling SRPE05, but we could not confirm the SRPE03’s lug width, so it is left out of the table.
The Seiko is 3.2mm wider and 0.4mm thicker, but only 0.9mm longer from lug tip to lug tip.
Dial
The Orient’s dial is gray with a gradient, with luminous hands and hour markers and a day-date. Orient’s spec sheet says little more, so we will not add details it does not confirm.
The King Turtle’s black dial carries its squared pattern, applied indices, LumiBrite and a diver’s 200m marking, with the day and date under the magnifier.
The Seiko’s dial is the more interesting surface. Buyers who dislike magnifiers will prefer the Orient. This round is even.
Crystal
Both watches use sapphire, which resists the fine scratches of daily wear far better than mineral glass. This row is a tie.
Accuracy
Orient rates the F6922 at +25/−15 seconds a day. Seiko rates the 4R36 at +45/−35. The Orient’s tolerance window is 40 seconds wide, and the Seiko’s is 80.
A rating is the range a maker will accept, not a promise about any individual watch, but the Orient’s is clearly tighter. Our guide to reading a watch spec sheet explains how to weigh it.
Water Resistance
This is the row that separates the two watches.
Both are rated to 200m with screw-down crowns. But Orient does not call this watch a diver’s watch. Its page lists 200m of water resistance and makes no claim to ISO 6425, the international standard for divers’ watches.
The King Turtle is a diver’s watch. Its dial reads “Divers 200m,” and Seiko’s instructions for its 4R35 and 4R36 diver’s models say the watch “can be used for air diving” within the range shown on the dial. Air diving means ordinary scuba on compressed air, as distinct from the saturation diving done by commercial divers. With no Seiko page left for the SRPE03, we could not confirm an explicit ISO claim, but the marking and the manual put it in a different category from the Orient.
An ordinary water resistance rating is a test pressure applied to a sample of new watches. The ISO diver’s standard calls for every watch to be tested and adds requirements for a timing bezel, legibility in the dark and resistance to shock and magnetism.
Both watches are rated to 200m. Only one of them is rated for diving.
Who needs that? Anyone who scuba dives, and especially anyone who would time a dive on the bezel or wear the watch as a backup to a dive computer. For swimming, snorkeling and everyday wear, the Orient’s 200m rating and screw-down crown are more than enough.
The Seiko wins this row clearly. Within Orient’s range, the ISO 6425 rated option is the Orient Star Sports Diver RE-AU0301B00B, listed at $700 but out of stock at Orient Watch USA when we checked.
On the Wrist
By diameter, the Orient is smaller by 3.2mm, and a 41.8mm case suits more wrists than a 45mm one. But the two are within a millimeter of each other from lug tip to lug tip, 46.8mm against 47.7mm, and lug-to-lug length usually decides whether a watch overhangs the wrist.
So the King Turtle is broader rather than longer. It will look larger, but on paper a wrist that takes the Orient should come close to taking the Seiko. Its crown at 4 o’clock also stays clear of the back of the hand.
Quality
The King Turtle has a ceramic bezel insert, a notched steel bezel, a solid engraved caseback and a three-link bracelet whose three-fold clasp adds a secure lock, a push-button release and a diving extension for wear over a wetsuit sleeve.
The Orient’s 316L steel bracelet closes with a fold-over clasp and a diver’s safety. Orient does not name the bezel insert material. The Seiko takes Best Build.
Long-Term Ownership
Both makers offer 3 years of warranty cover in the US. Seiko’s applies to purchases made from July 1, 2024 through Seiko or an authorized US dealer, so the seller of any King Turtle is worth checking. An Orient bought from Orient Watch USA has no such question.
The King Turtle’s ceramic insert is a lasting advantage over an insert whose material Orient does not name. Both watches have sapphire crystals and screw-down crowns, and both use widely serviced calibers, so neither should be hard to keep running.
Value
At $390, the Orient brings a sapphire crystal, 200m of water resistance, a screw-down crown, a 120-click bezel, a day-date and the tighter accuracy rating, in the narrower case, at a price its maker charges today.
The King Turtle’s value depends on what a retailer asks. It adds a diver’s rating, a ceramic insert, a solid caseback, a diving extension and a stronger design identity. The closer its price sits to the Orient’s $390, the easier it is to recommend.
For a current Seiko diver at a published price, read the Kamasu against the Prospex SRPF03. For the Mako-3 against Citizen‘s ISO compliant diver, see Orient Mako vs. Citizen Promaster.
Verdict
- Best Value
- Orient Mako (AA08, gradient dial)
- Best Movement
- Orient Mako (AA08, gradient dial)
- Best Build
- Seiko Prospex King Turtle
- Editor’s Pick
- Seiko Prospex King Turtle
The King Turtle is the better dive watch and our pick, with one condition. It is a diver’s watch rated for air diving, and it pairs that rating with a ceramic insert, a solid caseback and a diving extension, which earn it Best Build. If you dive, or simply want the most complete tool watch here, and you can buy one from an authorized dealer at a price you are comfortable with, choose the Seiko.
The Orient earns Best Value and a narrow Best Movement on its tighter accuracy rating. It is the narrower watch, it is sold new by its maker for a known $390, and for swimming and daily wear its 200m rating is more than enough. If the King Turtle you have found costs much more than that, or comes without Seiko’s US warranty, the Orient is the sensible buy.
