The Cartier Santos and Omega Speedmaster Professional suit different priorities: the Santos is a rounded-square, time-only watch in the cited configuration, while the Speedmaster Moonwatch Professional is a manually wound chronograph with a tachymeter. For a meaningful comparison, start with the exact references: here, the large automatic steel Santos WSSA0018 and the Hesalite steel Speedmaster 310.30.42.50.01.001. Their dimensions, functions, and water-resistance ratings differ, and neither is a universal winner.
How the Santos and Speedmaster differ
Cartier describes the Santos signature as a square case with rounded corners and visible screws. The Moonwatch Professional takes a different approach: Omega’s cited reference has a chronograph, small seconds, and tachymeter scale. The Santos WSSA0018 is time-only in its standard configuration.
The design distinction reflects two different propositions rather than two versions of the same tool watch. Cartier attributes the Santos origin to Louis Cartier’s 1904 response to aviator Alberto Santos-Dumont’s wish to tell time while flying; that is Cartier’s account of its own history.
Size and wrist fit: compare more than case width
The large Santos WSSA0018 is 39.8 mm wide and 9.38 mm thick. Omega’s 310.30.42.50.01.001 measures 42 mm in diameter, 47.50 mm lug-to-lug, and 13.54 mm thick. Cartier’s case-width figure and Omega’s diameter are not directly equivalent because their case shapes and measurement conventions differ.
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#1 Best Overall
- Classic Square Design: Adopts a square dial design with slightly rounded corners. The dial has Roman numeral hour markers from I to XII, classic design style that is clear and easy to read
- Strap & Size: Available in both leather and steel straps to ensure comfort and Sturdy, perfect for everyday wear or formal occasions. Dial diameter: 33mm, the watch can adjust the steel band length from 14.5 cm to 20 cm, suitable for most of Men’s wrist
- Precision Movement: Japanese quartz movement, provides precise and accurate time keeping
- Daily Water Resistant: In general, this watch can withstand splashes or brief immersion in water. However, it is not recommended for swimming or bathing
- Product Quality Suppor: We commit to reliable product quality assistance. Your trust means everything to us
On paper, the cited Santos is slimmer. The Speedmaster’s lug-to-lug measurement helps describe how far it spans the wrist, while the Santos’s rounded-square outline distributes its presence differently. Try the exact reference on your wrist if fit is a deciding factor; a single width number cannot settle which will wear better.
Cartier also makes a medium automatic steel Santos, reference WSSA0029, measuring 35.1 mm wide and 8.83 mm thick. Its smaller case may be worth considering if the large Santos seems too broad, but it is a separate reference and should be assessed on its own fit and configuration.
Rank #2
- Precise Japan Quartz Movement - Accuracy: +/-20 seconds per month
- Stainless Steel Case and Band, Push Button Release Clasp
- Mineral Crystal, 3-Hand Analog Display
- Case Size: 22 mm Diameter, 7.5 mm Thickness
- Water Resistant - 30 M
Movement and everyday operation
Cartier Santos WSSA0018
The cited large Santos is automatic and uses Cartier calibre 1847 MC. It winds itself through wrist motion while being worn; it is not a chronograph in this configuration. Cartier says the calibre has protection against everyday magnetism up to 1,500 gauss on its collection page.
Omega Speedmaster Professional 310.30.42.50.01.001
The cited Speedmaster uses the manually wound Omega calibre 3861. It has a chronograph and tachymeter, a 50-hour power reserve, and Master Chronometer certification with approval by METAS. Omega specifies resistance to magnetic fields reaching 15,000 gauss for this reference. The figures describe the named movements and models, not every watch in either collection, and do not establish a comparative reliability winner.
Rank #3
- SMALL TWO-TONE DESIGN: This square silver gold plated women watch designed by a smaller case size: case length: 0.78in, case width: 0.78in, boasts a sleek design highlighted by its elegant bracelet, perfectly complementing every outfits from casual to formal
- TINY ROMAN DIAL DISPLAY: Its Roman numeral dial not only adds a retro touch but also ensures easy readability, making it a sophisticated choice for daily wear
- WATCH MATERIAL: The two-tone watchband is designed for comfortable long-lasting wear; imported Japanese quartz movement offers reliable timekeeping. 3ATM waterproof can meet daily use demand
- DAINTY VINTAGE TWO-TONE BRACELET: This petite watch designed to be compact and suitable for women, characterized by a smaller case size and a gold-tone finish, providing a dainty and vintage look, best gift choice
- Customer Service: Offers peace of mind with a satisfaction shopping experience, if the purchase does not meet expectations, pls contact us at any time
Choose the Santos if you prefer an automatic, time-only watch; choose the Speedmaster if manual winding and chronograph timing are part of the appeal. The practical difference is the winding routine and the functions you will actually use.
Water resistance and daily wear
The large automatic Santos WSSA0018 is rated to 10 bar (approximately 100 metres), while the cited Speedmaster reference is rated to 5 bar (50 metres). These are manufacturer ratings, not blanket swimming recommendations. Follow the instructions for the exact model and its manual, and account for service condition before exposing a watch to water.
Rank #4
- CLASSIC ROMAN NUMERAL DESIGN WITH BLUE HANDS – White dial features bold Roman numerals and striking blue hands for a timeless, elegant look. Three separate sub-dials track hours, week, and date. High-hardness scratch-resistant glass keeps the dial clear. A sophisticated style for both business and casual occasions
- AUTOMATIC SELF-WINDING MOVEMENT – Powered by wrist motion, no battery needed. Manual winding also available: turn the crown up to 20 turns to fully charge the mainspring. Reliable mechanical movement keeps accurate time. Avoid adjusting the date between 9 PM and 3 AM to protect the calendar mechanism
- COMFORTABLE PU LEATHER STRAP – Soft, flexible, and odor-free PU leather strap fits comfortably for all-day wear. Case diameter 40mm, thickness 15mm, band width 20mm. Fits wrist sizes 5.5 to 8 inches. Lightweight at 95g for effortless daily wear
- SPLASH-RESISTANT FOR DAILY USE – Rated 1ATM (10 meters/33 feet), this watch withstands hand-washing and light splashes. Perfect for daily wear, business meetings, and travel. Note: Not suitable for swimming, showering, or submersion in water
- VERSATILE ACCESSORY FOR ANY OCCASION – Transitions seamlessly from office to weekend. Makes an ideal gift for birthdays, anniversaries, Father's Day, and holidays. A reliable timepiece that combines classic aesthetics with practical functionality for the modern man
Do not assume every Santos shares the WSSA0018 rating: Cartier lists other Santos variants, including small quartz models, with lower water resistance. Reference-specific guidance matters more than the collection name.
Crystal, caseback, bracelet, and straps
The cited Speedmaster 310.30.42.50.01.001 has a Hesalite crystal, a solid caseback, and 20 mm between the lugs. Omega also offers a sapphire Moonwatch Professional variant, reference 310.30.42.50.01.002, described on its regional collection page; the sapphire version has a transparent caseback. Bracelet and strap configurations vary, so verify the exact reference and local availability before purchase.
Best Value
- From the Bulova Men's Classic Collection, inspired by vintage design, our classic watches achieve a tailored, understated look that's always in style.
- 3 Hand, Calendar, Slim Movement
- Silver-Tone Stainless Steel Case with Black Croc Embossed Leather Strap
- Metalized Mineral Crystal
- 30M Water Resistant and 3 Year Limited Warranty
The WSSA0018 comes with a steel bracelet featuring Cartier’s SmartLink adjustment system and a second calfskin strap. Its QuickSwitch system supports strap changes. Check compatibility by reference before buying a replacement strap or bracelet component; fitting should not be presumed across generations or variants.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Which watch is more practical for you?
- For a time-only automatic: The cited Santos WSSA0018 combines automatic winding with a slimmer case and 10-bar rating.
- For timing functions: The Speedmaster adds a chronograph and tachymeter, but requires manual winding and has a lower stated water-resistance rating than the cited Santos.
- For a smaller Santos option: Consider the medium WSSA0029, whose published width and thickness are 35.1 mm and 8.83 mm.
- For crystal preference: Choose between the Hesalite reference and the sapphire variant only after confirming the exact product configuration, including caseback.
- For magnetic-field specifications: Cartier states up to 1,500 gauss for calibre 1847 MC; Omega specifies 15,000 gauss for the cited Speedmaster reference. These are manufacturer claims for distinct models and movements.
There is no defensible price winner from the available official pages: Omega’s collection page is regional and displays South Korean won, while no comparable Cartier price for the same market was established. Compare current local retail prices for the exact references if cost is decisive.
Specifications for the cited references
| Specification | Cartier Santos WSSA0018 | Omega Speedmaster 310.30.42.50.01.001 |
|---|---|---|
| Style and functions | Rounded-square, time-only automatic | Chronograph, small seconds, tachymeter |
| Movement | Automatic calibre 1847 MC | Manual-winding calibre 3861 |
| Case measurement | 39.8 mm wide | 42 mm diameter; measurements use different case conventions |
| Thickness | 9.38 mm | 13.54 mm |
| Lug-to-lug | Not stated by Cartier on the cited product page | 47.50 mm |
| Crystal and caseback | Not stated in the cited specifications | Hesalite; solid caseback |
| Water resistance | 10 bar (approximately 100 metres) | 5 bar (50 metres) |
| Bracelet or strap details | Steel bracelet with SmartLink adjustment; second calfskin strap with QuickSwitch | 20 mm between lugs; configurations vary by reference |
| Power reserve | Not stated in the cited specifications | 50 hours |
Specifications are manufacturer claims for these specific references. Collection variants and availability can change; consult the current product page and model documentation for the market where you plan to buy.
Quick Recap
Sources
- Cartier Santos collection
- Cartier Santos WSSA0018 product page
- Cartier Santos WSSA0029 product page
- Omega Speedmaster 310.30.42.50.01.001 product sheet
- Omega Speedmaster Moonwatch Professional collection page
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.
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