Description
SEIKO 5 Sports Field GMT Sports Style SBSC011 Automatic Men’s Watch
The SEIKO 5 Sports SBSC011 expands the practical Field Series design with a mechanical GMT movement, allowing the wearer to display a second time zone through a prominent red 24-hour hand. This Japanese-market model combines a highly legible black dial, a fixed 24-hour bezel and a stainless steel multi-link bracelet in a compact 39.4 mm case.
Developed as the first GMT model in the SEIKO 5 Sports Field Series, the SBSC011 preserves the collection’s versatile field-watch proportions while adding the functionality of SEIKO’s automatic Caliber 4R34. It is designed for everyday wear, travel and outdoor leisure rather than professional diving.
Black Field Dial with Red GMT Hand
The black dial uses bold Arabic hour numerals and a clearly defined minute track to support quick reading. Its large hour and minute hands are proportioned to match the practical Field Series design, while LumiBrite on the hands and indexes improves visibility in darker environments.
A five-sided red GMT hand provides a strong visual contrast against the black dial. The GMT hand completes one rotation every 24 hours and is read against the 24-hour scale on the fixed bezel, allowing a second time zone to be displayed alongside the primary local time.
A framed date window is positioned at 3 o’clock. The date, central seconds and red GMT hand give the dial additional functionality without removing the straightforward character of a traditional field watch.
Mechanical GMT Caliber 4R34
The SBSC011 is powered by SEIKO’s Caliber 4R34, a mechanical automatic movement that can also be wound manually through the crown. Movement of the wearer’s wrist winds the mainspring during normal use, while manual winding allows the watch to be restarted or given additional power when required.
Caliber 4R34 operates at 21,600 vibrations per hour, equivalent to six beats per second, and uses 24 jewels. When fully wound, it provides a power reserve of approximately 41 hours.
SEIKO specifies an accuracy range of +45 to −35 seconds per day when the watch is worn on the wrist within a temperature range of 5°C to 35°C. As with any mechanical watch, the actual daily rate can vary according to wearing conditions, position, temperature and the remaining mainspring power.
The movement includes a 24-hour hand for dual-time display, a date calendar and a stop-seconds function for more precise time setting.
Compact Stainless Steel Field Case
The stainless steel case measures 39.4 mm in diameter, 47.9 mm from lug to lug and 13.6 mm thick. These dimensions retain the wearable proportions associated with the Field Series while accommodating the additional mechanical GMT components.
A thick, curved Hardlex crystal rises above the bezel and contributes to the watch’s distinctive profile. The fixed bezel carries the 24-hour scale used with the red GMT hand and gives the model a functional travel-watch appearance without adopting an oversized case.
The crown is positioned near 4 o’clock in the familiar SEIKO 5 Sports configuration. This placement helps keep the crown away from the back of the wearer’s hand during normal use.
Multi-Link Stainless Steel Bracelet
The SBSC011 is fitted with a stainless steel multi-link bracelet. Its closely spaced links are designed to follow the wrist comfortably while giving the watch a more refined appearance than a conventional field-watch strap.
The bracelet is secured by a three-fold clasp with push-button release and an additional security lock. It has a 20 mm attachment width and accommodates a wrist circumference of up to approximately 205 mm before sizing.
See-Through Case Back
A see-through screw case back allows the mechanical Caliber 4R34 and its automatic winding rotor to remain visible. The transparent back emphasizes the watch’s mechanical construction while retaining the secure screw-back arrangement specified for the model.
Due to the manufacturing process, the final orientation of the case-back markings may vary between individual watches.
10-Bar Everyday Water Resistance
The SBSC011 offers 10-bar water resistance and magnetic resistance rated at 4,800 A/m on the corresponding international model. These specifications support normal daily wear and a broad range of recreational activities.
Despite its sporty construction, the SBSC011 is not an ISO-certified diver’s watch. It does not have the screw-down crown or professional diving specification associated with SEIKO’s dedicated diver models and should not be marketed as a diving watch.
Japanese Reference and International Counterpart
SBSC011 is the reference used for the Japanese domestic market. SEIKO distributes the corresponding black-dial Field GMT internationally as SSK023 or SSK023K1. Both references use the same Caliber 4R34, case dimensions, dial layout, bracelet configuration and core specifications.
The SBSC011 is manufactured in Japan, but its international distribution means it should not be called a Japan-exclusive design. It is a regular-production model and is not identified by SEIKO as a limited or numbered edition.
Key Highlights
- Japanese-market SEIKO 5 Sports Field Series reference SBSC011
- International counterpart SSK023/SSK023K1
- Black field-style dial with a contrasting red GMT hand
- Mechanical automatic Caliber 4R34 with manual winding
- Dual-time display using a 24-hour hand and fixed 24-hour bezel
- Approximately 41-hour power reserve
- Compact 39.4 mm stainless steel case
- Curved Hardlex crystal
- LumiBrite on the hands and indexes
- Stainless steel multi-link bracelet
- See-through screw case back
- 10-bar water resistance
- Made in Japan
- Regular-production model, not a limited edition
Product Specifications
| Brand | SEIKO |
|---|---|
| Collection | SEIKO 5 Sports |
| Series | Field Series |
| Style | Field Sports Style GMT |
| Model | SBSC011 |
| International Reference | SSK023 / SSK023K1 |
| Market | Japanese Domestic Market reference |
| Gender | Men’s |
| Dial Color | Black |
| GMT Hand | Red five-sided 24-hour hand |
| Caliber | 4R34 |
| Movement | Mechanical automatic with manual winding |
| Frequency | 21,600 vibrations per hour (6 beats per second) |
| Jewels | 24 |
| Power Reserve | Approximately 41 hours |
| Accuracy | +45 to −35 seconds per day when worn on the wrist at 5°C to 35°C |
| Functions | 24-hour dual-time hand, date display and stop-seconds |
| Case Material | Stainless steel |
| Case Diameter | 39.4 mm |
| Lug-to-Lug | 47.9 mm |
| Thickness | 13.6 mm |
| Crystal | Curved Hardlex |
| Bezel | Fixed bezel with 24-hour scale |
| LumiBrite | Hands and indexes |
| Bracelet | Stainless steel multi-link bracelet |
| Clasp | Three-fold clasp with push-button release and secure lock |
| Band Width | 20 mm |
| Maximum Wrist Circumference | Approximately 205 mm |
| Water Resistance | 10 bar |
| Magnetic Resistance | 4,800 A/m |
| Weight | Approximately 147 g |
| Case Back | See-through screw case back |
| Country of Manufacture | Japan |
| Release Date | January 12, 2024 |
| JAN | 4954628465405 |
| Edition | Regular production; not a limited edition |