The Seiko Prospex SPB153 is the green-dial version of Seiko’s modern 1970 Heritage Diver’s Watch: a 200 m diver with a 42.7 mm steel case, a 6R35 automatic movement and an officially listed power reserve of about 70 hours. “Captain Willard” is a popular nickname tied to the vintage Seiko 6105 and its appearance in Apocalypse Now; it is not Seiko’s official name for the SPB153.
What is the Seiko SPB153?
Seiko identifies the SPB153 as its “1970 Heritage Diver’s Watch.” Introduced in 2020, it is a modern Prospex interpretation of the 6105-era diver design. Seiko framed that year’s diver releases as part of the 55th anniversary of its dive-watch line, pairing heritage-inspired designs with updated specifications.
The “Captain Willard” label comes from watch coverage connecting the 6105 to Martin Sheen’s character in Apocalypse Now. Hodinkee used the nickname in its 2020 launch coverage when describing the SPB153 and its black-dial counterpart. Treat it as a familiar collector and editorial shorthand, not as the manufacturer’s formal model name.
SPB153 specifications
| Specification | Seiko’s listed detail |
|---|---|
| Case | Stainless steel |
| Diameter | 42.7 mm |
| Lug-to-lug | 46.6 mm |
| Thickness | 13.2 mm |
| Lug distance | 20 mm |
| Crystal | Curved sapphire, with anti-reflective coating on the inner surface |
| Movement | Caliber 6R35, automatic with manual winding |
| Power reserve | Approximately 70 hours |
| Other movement details | 24 jewels, stop-seconds and date display |
| Stated precision | +25 to −15 seconds per day |
| Water resistance | 200 m / 660 ft diver’s water resistance |
| Bezel and crown | Unidirectional rotating bezel; screw-down crown |
| Lume | LumiBrite on hands, indices and bezel |
| Band | Silicone |
These are specifications on Seiko’s current SPB153 product page. Its stated precision range is the manufacturer’s specification, not a guarantee that every individual watch will keep time at the same rate in all conditions.
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#1 Best Overall
- ELEGANT DESIGN: Round stainless steel case with blue rotating bezel, white dial and steel bracelet for a professional and refined look
- GMT function: Automatic movement with GMT function for monitoring two time zones, ideal for international travelers
- TECHNICAL SPECIFICATIONS: Diver watch with water resistance up to 300 m, sapphire crystal and date indicator
- SPECIAL EDITION: Prospex Collection 60th Anniversary commemorative model, representing Seiko excellence in the sports watch industry
- BRACELET: Solid stainless steel bracelet with safety clasp, perfect for everyday wear and sports activities
How does it wear?
The 42.7 mm diameter gives only part of the fit picture. At 46.6 mm lug-to-lug and 13.2 mm thick, the case’s length and height are also worth comparing against a watch you already find comfortable. Worn & Wound described the case contours and relatively slim profile as comfortable, but that is a reviewer’s subjective assessment rather than a universal fit result.
The supplied silicone band attaches at a 20 mm lug distance. That measurement can help when looking at replacement straps, but it does not establish the fit or quality of any particular aftermarket option; check the strap’s stated width and end shape before buying.
Rank #2
- KHAKI GREEN DIAL: this rugged sports watch features a khaki green dial patterned to mirror the shape of the bezel’s edge, with Lumibrite dial indicator hands and markers for low light and a magnified day/date calendar
- BLACK BEZEL: this versatile men’s watch features a black ceramic unidirectional bezel with distinctive scalloped edging, for elapsed timing
- AUTOMATIC & MANUAL: SRPE05 automatic watches for men power up with your natural movements, and feature the ability to wind manually, with 41 hours of reserve power
- WATER-RESISTANT: these rugged stainless steel dive watches for men feature a khaki green silicon strap, and are both stylish and robust, following ISO standards for scuba, and are water-resistant to 200 meters
- 4R36 CALIBER: equipped with the reliable 4R36 caliber, these precise men’s wrist watches ensure the most accurate timekeeping
SPB153 versus SPB151
The supported distinction between these two references is their colorway: the SPB153 has a green dial and bezel, while the SPB151 is black. The launch coverage describes them as companions in the same modern 6105-inspired family. The available specifications here do not establish other differences, so color is the safe basis for choosing between them.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Price and availability
Seiko’s UK product page displayed a price of £1,050 when checked for this article. That is a regional, time-sensitive listing—not a global or permanent price. Confirm the current price, stock and model availability with Seiko or a retailer in your market before purchasing.
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Rank #4
- WATER-RESISTANT: these water-resistant men's dive watches are ISO scuba-approved to depths of 200 meters
- AUTOMATIC: these self-winding, automatic men's watches are powered by your movement, with a power reserve of 41 hours
- STAINLESS STEEL: features a durable 43.8mm stainless steel watch case and bracelet.
- LUMIBRITE DISPLAY: this men's automatic watch features a highly-legible display with LumiBrite hands and markers
- 4R35 CALIBER: equipped with the reliable caliber 4R35 automatic movement, this accurate men's watch keeps precise time
Rank #3
- STAINLESS STEEL CASE built to endure with style, making this watch your perfect daily companion
- AUTOMATIC MOVEMENT for seamless precision in every tick of this watch
- SCRATCH-RESISTANT CRYSTAL to maintain a pristine look even with daily wear and tear on your watch
- LUMINESCENT HANDS for effortless readability in low-light conditions, ensuring you never miss a moment with this watch
- WATER RESISTANT DESIGN ensuring your watch is ready for any adventure, rain or shine
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.
