What’s actually slowing this PC down?
Pick the symptom - the matching free tool is one click away.
The Seiko Prospex SPB317J1 is listed at $900 on Seiko’s US site; the specific Blancpain Fifty Fathoms Bathyscaphe compared here, reference 5100 1140 O52A, is listed at $12,500 on Blancpain’s US site. The Blancpain is smaller and thinner, while its stated power reserve is longer. Both have date displays and unidirectional bezels, but their specifications and price points make this a comparison of distinct watches, not equivalent alternatives.
Which Bathyscaphe is being compared?
“Bathyscaphe” names a family, not one fixed specification. The Blancpain in this comparison is reference 5100 1140 O52A, the 38 mm steel, blue-dial version listed on Blancpain’s US product page. Its details should not be generalized to every Bathyscaphe.
| # | Preview | Product | Price | |
|---|---|---|---|---|
| 1 |
|
SEIKO SRPB41 Automatic Watch for Men - Presage Cocktail Time - Patterned Blue Dial with Date... | $399.00 | Buy on Amazon |
Seiko SPB317J1 vs. Blancpain Bathyscaphe: specifications
| Specification | Seiko Prospex SPB317J1 | Blancpain Bathyscaphe 5100 1140 O52A |
|---|---|---|
| Manufacturer-listed US price | USD 900 (Seiko US product page) | USD 12,500 (Blancpain US product page) |
| Case material and diameter | Stainless steel; 41.0 mm | Steel; 38.00 mm |
| Thickness | 12.3 mm | 10.80 mm |
| Lug-to-lug | 46.9 mm | Not stated on the cited product page |
| Movement | Automatic with manual winding, caliber 6R35 | Automatic, caliber 1150 |
| Power reserve | Approximately 70 hours | 100 hours |
| Published precision | +25 to -15 seconds per day | Not stated on the cited product page |
| Water resistance | 200 m / 660 ft, diver’s | 30 bar |
| Crystal and case back | Curved sapphire crystal; screw case back | Sapphire crystal and sapphire back |
| Strap and width | Silicone band; 20 mm between lugs | Sail-canvas strap option; 20 mm between horns |
| Other listed details | Date; unidirectional rotating bezel | Date; unidirectional bezel with ceramic insert and Liquidmetal hour markers; 28 jewels |
Specifications and listed prices are from the respective Seiko US product page and Blancpain US product page. Listed prices are manufacturer prices for the US pages, not guaranteed transaction prices in every market; prices and availability can change.
How the case dimensions differ
The Seiko measures 41.0 mm across, 12.3 mm thick and 46.9 mm lug-to-lug. Blancpain’s cited reference is 38.00 mm across and 10.80 mm thick. Blancpain does not state lug-to-lug on the cited page, so that measurement cannot be compared from these specifications alone.
#1 Best Overall
- STUNNING BLUE DIAL: this automatic men's watch features a deep blue, pressed pattern and gloss finish surrounded by a stainless steel watch case
- 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 stainless steel watch case and bracelet with see through caseback
- WATER-RESISTANT: these men's wrist watches are water-resistant down to 50 meters
- 4R35 CALIBER: equipped with the reliable caliber 4R35 automatic movement, this accurate men's watch keeps precise time
On the published dimensions, the Bathyscaphe has the smaller diameter and lower thickness. The SPB317J1’s listed 20 mm lug width and Blancpain’s 20 mm width between horns indicate the nominal strap width for each watch; those figures do not establish that a particular replacement strap will fit both.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Movement, reserve and stated precision
Seiko equips the SPB317J1 with automatic caliber 6R35, which can also be wound manually. Seiko gives an approximate 70-hour power reserve and a stated precision range of +25 to -15 seconds per day. Blancpain lists automatic caliber 1150, a 100-hour reserve and 28 jewels for this reference; its cited page does not state a precision range.
These are manufacturer specifications, not independent comparative test results. The Blancpain’s published reserve is 30 hours longer, but the available figures do not establish how accurately either individual watch will run in everyday use.
Water resistance and diver details
Seiko specifies 200 m / 660 ft diver’s water resistance for the SPB317J1. Blancpain specifies 30 bar for reference 5100 1140 O52A. These are the manufacturers’ published ratings; they should not be read as a guarantee of suitability for every dive, depth, or condition. Follow the applicable owner guidance for use and care.
Both watches have a date and a unidirectional bezel. The Seiko page lists a curved sapphire crystal, silicone band and screw case back. Blancpain lists a sapphire crystal and back, a sail-canvas strap option, and a ceramic bezel insert with Liquidmetal hour markers.
What the listed prices do—and do not—tell you
The official US pages place the SPB317J1 at USD 900 and this specific Bathyscaphe at USD 12,500. That substantial difference is useful context, but a price listing alone does not establish comparative finishing, durability, service costs, comfort or resale value. Those qualities are not established by the specifications cited here.
Blancpain describes this model as one that “blends refined elegance with diving performance.” That is the manufacturer’s description of the cited 38 mm Bathyscaphe, rather than an independent assessment.
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.
