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Seiko watch · Cocktail Time · automatic

Seiko SRPE43

The Seiko SRPE43 measures 38.5 mm across, 45.4 mm lug to lug, and 11.8 mm thick, with 20 mm lugs. It fits wrists from ~16 cm (flat-fit estimate).

Sources checked · How we source numbers
Case
38.5 mm1
Lug to lug
45.4 mm1
Thickness
11.8 mm1
Lug width
20 mm1
Seiko SRPE43: size drawingSeiko SRPE43, round case, top and side view to scale: case diameter 38.5 mm, lug to lug 45.4 mm, lug width 20 mm, thickness 11.8 mm. Bezel, dial and crown size are schematic.lug width 20Ø 38.5lug to lug 45.4TOPthickness 11.8SIDE
Seiko SRPE43, top and side, to scaleDrawing from data, not a photo · mm

Seiko SRPE43 specifications

Case diameter
38.5 mm1
Lug to lug
45.4 mm1
Thickness
11.8 mm1
Lug width
20 mm120 mm watches
Weight
63 g1
Crystal
Box-shaped Hardlex1
Water resistance
5 bar (50 m)1
Movement
Seiko 4R351 · automaticSeiko 4R35 specs
Battery
none: the Seiko 4R35 is automatic
Years made
start not published
Case code
not in our data yet
Line
Cocktail Time1

On your wrist

The verdict compares the lug to lug with the flat top of your wrist. Balanced from ~16 cm, past the edges below ~14.5 cm.

= 6.7 in

Balanced on a 17 cm wrist: the 45.4 mm lug to lug covers 83% of an estimated 54.8 mm flat top.

Flat top = circumference ÷ 3.1, a community convention, not a measurement of your arm. Compact ≤ 0.75 of the flat top, balanced ≤ 0.89, at the edge ≤ 1. Compare more watches in the watch size calculator.

Seiko SRPE43: wrist fitSeiko SRPE43 on a wrist, top view to scale. lug to lug 45.4 mm. Wrist 170 mm, estimated flat width 54.8 mm (circumference / 3.1). Ratio 0.83: balanced.wrist, flat topwrist flat ≈ 54.8lug to lug 45.4Balanced · 45.4 / 54.8 = 0.83estimate: wrist 170 / 3.1 = 54.8 flatcompactbalancededgeoverhang0.750.891
Seiko SRPE43 on a 17 cm wristDrawing from data, not a photo · mm

Actual size on your screen

Calibrate once with a bank card and the drawing shows the Seiko SRPE43 at 1:1, next to a millimetre ruler.

1:1 · not calibrated: sizes are approximate
Seiko SRPE43: size drawingSeiko SRPE43, round case, top and side view to scale: case diameter 38.5 mm, lug to lug 45.4 mm, lug width 20 mm, thickness 11.8 mm. Bezel, dial and crown size are schematic.lug width 20Ø 38.5lug to lug 45.4TOPthickness 11.8SIDE
Drawing from data, not a photo · mm
01020304050

Seiko SRPE43 strap size

Lug width 20 mm1: a 20 mm strap with 20 mm spring bars fits between the lugs. 62 other models take 20 mm.

Attachment: not published in our sources.

Find your strap length in the watch strap size tool, with the Seiko SRPE43 filled in.

On a bracelet? How to remove watch links to size it to your wrist.

20 mm strap: strap diagramTwo-piece strap laid flat (20 mm strap). Lug width 20 mm. Short piece — (unknown), long piece — (unknown). Buckle, keepers and holes are schematic.short —long —lug 20lug 20strap length —20 mm strap
20 mm at the lugs; lengths depend on your wristDrawing from data, not a photo · mm

Movement: Seiko 4R35

The Seiko SRPE43 runs on the Seiko 4R35, an automatic movement. 25 other models in our base use it.

Beat rate
21,600 bph2
Power reserve
41 h2
2 sources disagree; show every value
  • manufacturer 41 h2
  • secondary source 40, 41 h4
Jewels
232
2 sources disagree; show every value
  • manufacturer 232
  • secondary source 23, 244
Accuracy
−35 to +45 s/day3
Hacking seconds
Yes2
Hand winding
Yes2

Battery

none: the Seiko 4R35 is automatic

A mechanical watch has no cell to replace; it needs a service instead.

Same size as the Seiko SRPE43

The models nearest to the Seiko SRPE43 in case width and lug to lug, drawn over it to scale; below, every model within 1 mm of its 45.4 mm.

Size comparison: Seiko SRPE43, Dan Henry 1962 Racing Chronograph Black, Zelos Aurora Field 38 Aventurine, Seiko SPB155Top-view outlines to scale on one centre. A Seiko SRPE43: Ø 38.5, L2L 45.4, lug 20, T 11.8. B Dan Henry 1962 Racing Chronograph Black: Ø 39, L2L 45.9, lug 20, T 13.5 (vs A: Ø +0.5 L2L +0.5 lug 0 T +1.7). C Zelos Aurora Field 38 Aventurine: Ø 38, L2L 46, lug 20, T 12 (vs A: Ø −0.5 L2L +0.6 lug 0 T +0.2). D Seiko SPB155: Ø 38, L2L 46, lug 20, T 12.9 (vs A: Ø −0.5 L2L +0.6 lug 0 T +1.1).C Ø 38D Ø 38A Ø 38.5B Ø 39A L2L 45.4B L2L 45.9C L2L 46D L2L 46A Seiko SRPE43Ø 38.5 · L2L 45.4 · lug 20 · T 11.8B Dan Henry 1962 Racing Chronograph BlackØ 39 · L2L 45.9 · lug 20 · T 13.5vs A: Ø +0.5 L2L +0.5 lug 0 T +1.7C Zelos Aurora Field 38 AventurineØ 38 · L2L 46 · lug 20 · T 12vs A: Ø −0.5 L2L +0.6 lug 0 T +0.2D Seiko SPB155Ø 38 · L2L 46 · lug 20 · T 12.9vs A: Ø −0.5 L2L +0.6 lug 0 T +1.1
A Seiko SRPE43 and the 3 nearest in size, on one centre, to scaleDrawing from data, not a photo · mm

Nearest in size

  1. ASeiko SRPE43this watch
  2. BDan Henry 1962 Racing Chronograph BlackW +0.5 · L2L +0.5 · T +1.7 mm
  3. CZelos Aurora Field 38 AventurineW −0.5 · L2L +0.6 · T +0.2 mm
  4. DSeiko SPB155W −0.5 · L2L +0.6 · T +1.1 mm

Differences against A in mm: W case width, L2L lug to lug, T thickness. Nearest by width and length together, from the published sizes.

Same published case dimensions (3)Seiko SRPE41, Seiko SRPE45, Seiko SRPF41

Same movement: Seiko 4R35

All 26 models on the Seiko 4R35

Seiko SRPE43 questions

How big is the Seiko SRPE43?

The Seiko SRPE43 measures 38.5 mm across, 45.4 mm lug to lug, 11.8 mm thick, 63 g.

Will the Seiko SRPE43 fit a 6.5-inch wrist?

Balanced: the Seiko SRPE43's 45.4 mm lug to lug takes 85% of the ~53.3 mm flat top of a 6.5-inch (16.5 cm) wrist. By the same estimate (circumference ÷ 3.1) it sits balanced from about 16 cm and overhangs the flat top on wrists under about 14.5 cm.

Does the Seiko SRPE43 need a battery?

No. The Seiko SRPE43 has no cell to replace: a wound mainspring drives its automatic Seiko 4R35.

What movement is in the Seiko SRPE43?

The Seiko SRPE43 runs on the Seiko 4R35, an automatic movement.

What strap size does the Seiko SRPE43 take?

The Seiko SRPE43 measures 20 mm between the lugs, so it takes a 20 mm strap with 20 mm spring bars. 62 other models in our base share that width.

Find the strap length for your wrist and the Seiko SRPE43 in the watch strap size tool.

More Seiko watches

Sources

Documents checked · Report a wrong number

  1. 1Seiko Watch Corporation — SRPE43J1 product page (Presage), seikowatches.com US · html · read
  2. 2Seiko Watch Corporation — Instructions: Seiko Automatic Diver's Watch Cal. 4R15/4R16/4R35/4R36/7S26/7S35/7S36 (English) · pdf · read
  3. 3Seiko Watch Corporation — Instructions: Diver's Watch for Air Diving, Cal. 4R35 / 4R36 (English) · pdf · read
  4. 4Grail Watch — Grail Watch Reference: Seiko Cal. 4R35 · html · read
  5. 5Seiko Watch Corporation — Instructions: Mechanical watch, Cal. 4R35 / 4R36 / 4R37 / 4R38 / 4R71 / 4R72 / 4R39 (English) · pdf · read