Quick Answer
The Orient Kamasu out-specifies the Seiko 5 Sports in almost every measurable way — sapphire, 200 m, solid end links and a tighter accuracy window — for around $40 more. The Seiko wins on luminous performance, service network and aftermarket support.
These are the two watches most often recommended to someone buying a first automatic, and the recommendation usually comes down to whether you value specification or ecosystem.
Specification Comparison
Orient Kamasu
5 categories won
Seiko 5 Sports SRPD55
4 categories won
- Street price
- $235
- $195Winner
- Movement type
- Automatic
- Automatic
- Caliber
- F6922
- 4R36
- Power reserve
- 40 hours
- 41 hoursWinner
- Stated accuracy
- -15 to +25 seconds per day (Orient specification)Winner
- -35 to +45 seconds per day (Seiko specification)
- Case diameter
- 41.8 mm
- 42.5 mm
- Case thickness
- 12.8 mmWinner
- 13.4 mm
- Lug-to-lug
- 47 mm
- 46 mmWinner
- Crystal
- SapphireWinner
- Hardlex mineral
- Water resistance
- 200 m (656 ft)Winner
- 100 m (328 ft)
- Bracelet / strap
- Three-link bracelet with solid end links
- Three-link bracelet with folded end links
- Weight
- 160 g
- 148 gWinner
- Style
- Diver · Sport · Everyday
- Sport · Everyday · Diver
- Recommended wrist
- Medium · Large
- Medium · Large
- Selection Score
- 88 / 100Winner
- 85 / 100
Selection Time Verdict
Choose the Orient Kamasu
Choose the Orient Kamasu if you want the best specification your money can buy, if a sapphire crystal matters, or if you want a bracelet you do not have to replace.
Read the full reviewChoose the Seiko 5 Sports SRPD55
Choose the Seiko 5 Sports if you plan to modify the watch, if luminous performance matters, or if you want the brand with service centres everywhere.
Read the full reviewOn paper this is not close. The Kamasu has a sapphire crystal where the Seiko has Hardlex, 200 m where the Seiko has 100 m, solid end links where the Seiko has folded ones, and a published accuracy window of -15/+25 against Seiko's -35/+45. It costs about $40 more. The Seiko's case is that it is the centre of an ecosystem: parts, dials, bezels, straps and watchmakers who know it. If you want a watch to own, buy the Kamasu. If you want a watch to tinker with, buy the Seiko.
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Frequently Asked Questions
Which is better for a first automatic watch?
The Kamasu if you want the watch to feel finished out of the box; the Seiko if you expect to modify it or want the larger support network.
Are both suitable for swimming?
Yes. The Kamasu is rated to 200 m and the Seiko to 100 m, both with screw-down crowns. Neither is ISO 6425 certified.
Updated August 19, 2026