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Outbyte PC Repair FREEClear out junk files and repair common Windows errorsFree Scan →Outbyte Driver Updater FREEFix the driver behind crashes, sound loss and screen glitchesFind Drivers →The Seiko 5 Sports Time Sonar SRPJ45 and SRPJ47 share the same published movement, functions and case dimensions. The clearest difference is color: the SRPJ45 pairs a turquoise-blue dial treatment with blue and black bezel accents, while the SRPJ47 uses orange accents and an orange-tinted dial. Neither is a chronograph; both are automatic watches with day/date displays.
SRPJ45 vs. SRPJ47: the differences at a glance
| Feature | SRPJ45 | SRPJ47 |
|---|---|---|
| Dial treatment | Translucent turquoise-blue | Orange-tinted |
| Bezel accents | Blue and black | Orange accents |
| Seconds hand | Orange, according to a 2022 comparison | Yellow, according to a 2022 comparison |
| Movement and functions | 4R36 automatic; day/date and stop-seconds | 4R36 automatic; day/date and stop-seconds |
| Case dimensions | 42.5 mm diameter; 13.4 mm thick; 46.0 mm lug-to-lug | 42.5 mm diameter; 13.4 mm thick; 46.0 mm lug-to-lug |
| Regional listed price | USD 350 on Seiko’s US page | GBP 300 on Seiko’s UK page |
The color comparison is based on the official product descriptions and a December 2022 comparison of the two models. The seconds-hand colors are reported in that dated secondary comparison; Seiko’s official specifications establish the shared technical details. Prices are separate regional listing snapshots, not a direct price comparison, and may change. Seiko SRPJ45; Seiko SRPJ47; Watch Home comparison, December 7, 2022.
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|---|---|---|---|---|
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SEIKO SSK001 Automatic Watch for Men - 5 Sports GMT, SKX Series - Blue | $495.00 | Buy on Amazon |
What the two watches have in common
Both are Seiko 5 Sports SKX-series watches built around the 4R36 automatic movement, which can also be wound by hand. Seiko lists approximately 41 hours of power reserve and 24 jewels for each. The movement includes stop-seconds and a day/date display. SRPJ45 specifications; SRPJ47 specifications.
The shared published case and hardware specifications are:
#1 Best Overall
- BLUE DIAL: this handsome men’s watch features a striking deep blue dial with luminous dial indicator hands and markers and date calendar to keep you organized
- BLUE & BLACK BEZEL: with a 24-hour bezel and easy-to-read fourth hand, this GMT watch helps you keep time as you travel
- DURABLE UTILITY: these versatile men’s wrist watches feature a 42.5mm stainless steel watch case and bracelet, for a classic, timeless look.
- WATER-RESISTANT: this rugged sports watch is water-resistant up to 100 meters
- 4R34 CALIBER: equipped with the reliable 4R34 caliber, these automatic watches for men ensure the most accurate in self winding timekeeping, with 41 hours of reserve power and manual winding option
- Stainless-steel case, 42.5 mm in diameter and 13.4 mm thick
- 46.0 mm lug-to-lug length and 22 mm lug spacing
- Hardlex crystal
- Unidirectional rotating bezel
- See-through screw caseback
- 10 bar water resistance
Is the Seiko Time Sonar a chronograph?
No. The SRPJ45 and SRPJ47 are three-hand automatic watches with day/date displays, not chronographs. Their rotating bezels and seconds hands do not provide a chronograph function: Seiko lists neither a stopwatch complication nor chronograph controls among their functions. The 4R36’s stop-seconds feature means the seconds hand stops when setting the time; it is not a stopwatch.
How the Time Sonar design relates to the 1970s
Seiko describes the SRPJ45 as “A tribute to Seiko’s iconic ‘Time Sonar’ of the 1970s”. Its translucent turquoise dial reveals the day/date disk beneath, making the visible calendar mechanism part of the design. This is a design tribute; it does not establish that the modern watch mechanically reproduces a 1970s model. Seiko USA’s SRPJ45 description.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Which one should you choose?
Choose the SRPJ45 for blue and turquoise
The SRPJ45 is the more restrained color option of the pair, with a turquoise-blue dial treatment and blue/black bezel accents. Seiko’s description specifically calls attention to the translucent dial and the visible day/date disk.
Choose the SRPJ47 for orange
The SRPJ47 carries the warmer orange treatment, including an orange-tinted dial. A December 2022 comparison also identifies its seconds hand as yellow. The underlying published specifications do not indicate a performance advantage over the SRPJ45.
Check the case dimensions against your wrist
Both watches have a 42.5 mm diameter and 46.0 mm lug-to-lug length. Those figures are more useful for estimating how much wrist space the case spans than diameter alone, but they cannot establish personal comfort or fit. If possible, try the watch on before buying.
Compare prices only within the same market
Seiko’s US product page listed the SRPJ45 at USD 350, while its UK page listed the SRPJ47 at GBP 300. These are region-specific listed prices from separate pages, not a like-for-like comparison; local taxes, availability and later price changes may affect what a buyer pays.
Can you change the strap?
Both models have 22 mm lug spacing, so a 22 mm strap is a plausible replacement option. That measurement alone does not guarantee that every third-party strap, fitted end link or clasp will suit the watch. Check the strap’s connection style and dimensions before ordering.
What the published specifications do not tell you
Manufacturer specifications establish listed features and dimensions, but do not by themselves establish measured timekeeping accuracy, bracelet quality, bezel feel, comfort on a particular wrist or legibility in every lighting condition. Those points require direct handling or independent testing; no performance superiority between the SRPJ45 and SRPJ47 is established by the published specifications cited here.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
