Movements
Seiko 4R35 caliber reference
The date-only sibling of the 4R36, and the movement most people are actually buying.
By Stephen V. · Updated Jul 24, 2026
The Seiko 4R35 is an automatic movement with a date, running at 21,600 vph with a 41-hour power reserve and 23 jewels. It hacks and hand-winds. It is the same caliber Seiko Instruments sells externally as the NH35, and it is the 4R36 without the day wheel.
Published specification
| Specification | Value |
|---|---|
| Type | Automatic, bidirectional winding |
| Beat rate | 21,600 vph (6 beats/sec) |
| Jewels | 23 |
| Power reserve | Approx. 41 hours |
| Stated accuracy | -35 to +45 sec/day |
| Hacking | Yes |
| Hand-winding | Yes |
| Complications | Date, quickset |
Why you often want the 4R35 rather than the 4R36
The day complication costs money and dial space, and a great many people never read it. Where two references differ only in whether the movement is a 4R35 or a 4R36, the 4R35 version is usually cheaper and has a cleaner dial.
It also has one fewer thing to set. A day-date watch left unworn for a week needs both wheels advanced; a date-only watch needs one.
The 23-versus-24 jewel count is the day wheel’s bearing. It has no bearing, so to speak, on performance.
Watches that use it
- Prospex Samurai — SRPF03, SRPL15
- Presage Cocktail Time — SRPB43, SRPE41, SRPK46
- Prospex compact divers — SRPG57 and relatives
The relationship to the NH35, stated plainly
They are the same movement from the same manufacturer, with different stated regulation and different sales channels. The full comparison goes through what that does and does not mean for a buyer. The short version: a microbrand watch with an NH35 is not running a lesser engine than a Seiko with a 4R35.
The watches on this page
Specifications are transcribed from Seiko’s published documentation. Prices come from Amazon and carry the date they were verified. We have not handled these watches — here is what we did instead.
$525.0016% off
Price as of Jul 24, 2026. Prices move — Amazon's is the one that counts.
#ad · we may earn a commission from this link to Seiko Prospex Samurai SRPF03
Seiko Prospex Samurai SRPF03
SRPF03K1Best for: A 200 m diver with sharp, faceted case geometry
The angular one. A 200 m ISO diver with hard-cut case facets — the Seiko diver you buy when the Turtle is too round.
- Spec completeness for the price
- 8.8
- Movement relative to bracket
- 8.4
- Case proportions
- 8.6
- Strap flexibility
- 9.5
- Availability
- 8.3
What it gets right
- Slimmer than the Turtle at 12.8 mm
- Faceted case catches light in a way the rounder Seikos do not
- Full ISO 6425 diver rating
What it gets wrong
- Date only — no day, unlike the 4R36 references
- Hardlex
- Sharp lug edges are less forgiving on a small wrist
Skip this one if: you want the day complication. The Samurai runs the 4R35, which is the same movement as the 4R36 minus the day wheel.
| Case diameter | 43.8 mm |
|---|---|
| Lug-to-lug | 47.0 mm |
| Thickness | 12.8 mm |
| Lug width | 22 mm |
| Crystal | Hardlex (hardened mineral) |
| Water resistance | 200 m, ISO 6425 rated |
| Crown | Screw-down |
| Caliber | Seiko 4R35 |
| Type | Automatic, hand-winding and hacking |
| Beat rate | 21,600 vph (6 beats/sec) |
| Jewels | 23 |
| Power reserve | Approx. 41 hours |
| Stated accuracy | -35 to +45 sec/day |
| Complications | Date |
$450.0016% off
Price as of Jul 24, 2026. Prices move — Amazon's is the one that counts.
#ad · we may earn a commission from this link to Seiko Presage Cocktail Time SRPB43
Seiko Presage Cocktail Time SRPB43
SRPB43J1Best for: A dress watch that looks like it cost three times the money
The blue Cocktail Time. A box-shaped crystal over a deeply textured dial — the most expensive-looking watch Seiko sells at this price by a wide margin.
- Spec completeness for the price
- 8.6
- Movement relative to bracket
- 8.4
- Case proportions
- 8.5
- Strap flexibility
- 9.2
- Availability
- 8.4
What it gets right
- The box crystal distorts light at the edges the way vintage acrylic did
- Sunburst dial texture that photographs badly and looks superb in person
- Exhibition back
What it gets wrong
- 50 m, so it is not a swim watch
- 47.6 mm lug-to-lug is long for a 40.5 mm dress case
- Hardlex on a curved crystal is harder to polish than a flat one
Skip this one if: you need one watch for everything. At 50 m and on a leather strap this is a shirt-cuff watch — pair it with a diver rather than asking it to be one.
| Case diameter | 40.5 mm |
|---|---|
| Lug-to-lug | 47.6 mm |
| Thickness | 11.8 mm |
| Lug width | 20 mm |
| Crystal | Box-shaped Hardlex |
| Water resistance | 50 m — splash resistant, not for swimming |
| Display back | Yes — exhibition caseback |
| Caliber | Seiko 4R35 |
| Type | Automatic, hand-winding and hacking |
| Beat rate | 21,600 vph (6 beats/sec) |
| Jewels | 23 |
| Power reserve | Approx. 41 hours |
| Stated accuracy | -35 to +45 sec/day |
| Complications | Date |
Price as of Jul 24, 2026. Prices move — Amazon's is the one that counts.
#ad · we may earn a commission from this link to Seiko Prospex Diver SRPG57
Seiko Prospex Diver SRPG57
SRPG57K1Best for: A 200 m Seiko diver in a smaller case
A 200 m Prospex automatic in the modern compact diver case. The one to look at if the Turtle and Samurai both feel too wide.
- Spec completeness for the price
- 8.4
- Movement relative to bracket
- 8.4
- Case proportions
- 8.8
- Strap flexibility
- 9.2
- Availability
- 8.2
What it gets right
- 12.3 mm is slim for a 200 m Seiko diver
- 20 mm lugs open up a wider strap market than 22 mm
- Full ISO 6425 rating
What it gets wrong
- Hardlex
- Date only
- Seiko does not publish a lug-to-lug figure for this reference
Skip this one if: lug-to-lug is your buying constraint. Seiko does not publish it here, and we are not going to invent a number for you — measure one in person or start with a reference where the figure is documented.
| Case diameter | 42.4 mm |
|---|---|
| Lug-to-lug | Not published by Seiko for this reference |
| Thickness | 12.3 mm |
| Lug width | 20 mm |
| Crystal | Hardlex (hardened mineral) |
| Water resistance | 200 m, ISO 6425 rated |
| Crown | Screw-down |
| Caliber | Seiko 4R35 |
| Type | Automatic, hand-winding and hacking |
| Beat rate | 21,600 vph (6 beats/sec) |
| Jewels | 23 |
| Power reserve | Approx. 41 hours |
| Stated accuracy | -35 to +45 sec/day |
| Complications | Date |
Questions
Is the 4R35 the same as the NH35?
The same movement from the same manufacturer, differing in stated regulation and in which division sells it. Beat rate, reserve, jewel count and dimensions are identical.
Why does the 4R35 have 23 jewels and the 4R36 have 24?
The extra jewel is the day wheel’s bearing. Jewel count above a certain point is a function of how many complications a movement drives, not a quality measure.
Does the 4R35 hand-wind?
Yes, from the crown in the neutral position, and it hacks when the crown is pulled out. Both features distinguish it from the older 7S26.
Which is better, 4R35 or 4R36?
Neither. The 4R36 has a day complication and the 4R35 does not; performance is identical. Buy the one whose dial you prefer, and note that the date-only version is usually a little cheaper.
Sources
- Seiko Watch Corporation — US catalog and specifications
- Seiko Prospex collection — official specifications
- Seiko Instruments — movement division (NH-series manufacturer)
- Seiko instruction manuals and caliber documentation
Specifications are transcribed from manufacturer documentation and published standards. Where a manufacturer does not publish a figure, this page says so rather than estimating one.