Built for enthusiasts who appreciate a classic dive watch with serious specifications, the San Martin SN0154G 40mm Diver Watch combines a versatile stainless steel case, ST2130 automatic mechanical movement, ceramic bezel, sapphire crystal, and impressive 300M water resistance.

Available with Enamel Blue, Enamel Black, and Enamel Green dials, the SN0154G balances traditional dive-watch functionality with refined details such as GS-crafted hands, BGW-X1 blue lume, and an On-The-Fly adjustable clasp.

With its balanced 40mm case diameter and professional 30Bar water resistance, the SN0154G is designed to work equally well as a capable dive watch and a durable everyday mechanical timepiece.

ST2130 Automatic Mechanical Movement

Powering the San Martin SN0154G is the ST2130 automatic mechanical movement.

The automatic movement eliminates the need for a battery, winding itself through the natural motion of your wrist during regular wear.

For enthusiasts who appreciate the character and engineering of traditional mechanical watches, the ST2130 provides the mechanical heart behind the SN0154G's classic dive-watch design.

Combined with the watch's robust stainless steel construction and 300M water resistance, it creates a practical mechanical diver built for regular use.

Versatile 40mm Stainless Steel Case

Case size plays an important role in everyday comfort, and the SN0154G uses a well-balanced 40mm diameter.

Case Dimensions

• Case Diameter: 40mm
• Lug to Lug: 48mm
• Thickness: 13.2mm
• Case Material: Solid 316L Stainless Steel
• Weight: Approximately 163g

The 40mm diameter gives the watch enough presence for a serious dive watch without moving into oversized territory.

Its 48mm lug-to-lug measurement also helps maintain balanced proportions, making the SN0154G an attractive option for collectors looking for a 40mm automatic dive watch suitable for both everyday wear and outdoor use.

Enamel Dial in Blue, Black or Green

The dial is one of the standout visual features of the San Martin SN0154G.

Instead of limiting the collection to a single traditional dive-watch color, San Martin offers three enamel dial options:

• Enamel Blue
• Enamel Black
• Enamel Green

The black version delivers the most traditional and versatile look, while blue adds a richer maritime character. Green offers a more distinctive alternative for collectors looking to add some color to their watch collection.

The enamel-style surface gives the dial additional visual depth while maintaining the clean readability expected from a mechanical diver.

GS-Crafted Hands with BGW-X1 Blue Lume

The SN0154G features GS-crafted hands with luminous coating, bringing sharper detailing to the dial.

Both the hands and hour markers use BGW-X1 blue luminous material, producing a bright blue glow in darker environments.

This combination gives the watch strong visual contrast during the day while maintaining useful readability at night or in low-light conditions.

Luminous Features

• BGW-X1 blue lume
• Luminous hour markers
• Luminous hands
• Luminous marker at 12 o'clock on the bezel

For a dive watch, clear low-light readability is an essential part of the design rather than simply a decorative feature.

120-Click Ceramic Dive Bezel

Surrounding the dial is a 120-click rotating dive bezel with a ceramic top ring.

Ceramic is highly resistant to scratches and fading, making it an excellent choice for a watch intended for regular wear.

The bezel also includes a luminous marker at the 12 o'clock position, helping maintain visibility in darker environments.

The 120-click mechanism allows precise positioning when using the bezel to track elapsed time, reinforcing the functional dive-watch character of the SN0154G.

Sapphire Crystal with AR Coating

Protecting the enamel dial is a sapphire crystal with anti-reflective coating.

Sapphire provides excellent scratch resistance compared with conventional mineral glass, helping the watch maintain its appearance during long-term daily use.

The added AR coating helps reduce unwanted reflections and improves dial visibility under different lighting conditions.

Combined with the ceramic bezel and solid stainless steel case, sapphire crystal contributes to the durable construction expected from a 300M automatic dive watch.

300M Water Resistance

One of the most important specifications of the SN0154G is its 30Bar / 300 meters of water resistance.

This is supported by a robust dive-watch construction that includes:

• Screw-down crown
• Screw-down case back
• Solid 316L stainless steel case
• Sapphire crystal
• Ceramic dive bezel

The screw-down crown also features a 3D San Martin hexagon logo, adding a subtle branded detail to the case.

With 300M water resistance, the SN0154G offers considerably more capability than a typical everyday sports watch, making it suitable for swimming, snorkeling, diving, outdoor activities, and regular daily wear.

Solid 316L Stainless Steel Bracelet

The SN0154G comes fitted with a solid 316L stainless steel bracelet designed to complement the substantial dive-watch case.

The bracelet measures 20mm at the lugs and tapers to 16mm, giving the watch a more balanced profile around the wrist.

Bracelet Specifications

• Solid 316L stainless steel
• 20mm → 16mm taper
• Approximately 200mm / 7.9in length
• On-The-Fly adjustable clasp
• San Martin hexagon logo

The taper helps prevent the bracelet from feeling excessively bulky while retaining the solid construction expected from a mechanical sports watch.

On-The-Fly Adjustable Clasp

Everyday comfort is enhanced by an On-The-Fly adjustable clasp.

The system allows quick bracelet micro-adjustments, making it easier to fine-tune the fit without removing links or using tools for minor changes.

This is particularly useful for a dive and sports watch because wrist size can change slightly throughout the day due to temperature and physical activity.

Combined with the 20mm-to-16mm tapered bracelet, the OTF clasp helps make the SN0154G comfortable for extended daily wear.

San Martin SN0154G Specifications

Brand: San Martin
Model: SN0154G

Movement

• ST2130 Automatic Mechanical Movement

Case

• Solid 316L Stainless Steel
• Diameter: 40mm
• Lug to Lug: 48mm
• Thickness: 13.2mm

Crystal

• Sapphire Crystal Glass
• Anti-Reflective Coating

Bezel

• 120-Click Dive Bezel
• Ceramic Top Ring
• Luminous Marker at 12 O'clock

Dial Colors

• Enamel Blue
• Enamel Black
• Enamel Green

Hands & Lume

• GS-Crafted Hands
• Luminous Coating
• BGW-X1 Blue Lume
• Luminous Hands and Hour Markers

Crown

• Screw-down Crown
• 3D San Martin Hexagon Logo

Case Back

• Screw-down Case Back

Bracelet

• Solid 316L Stainless Steel
• Width: 20mm → 16mm
• Length: Approximately 200mm / 7.9in

Clasp

• On-The-Fly Adjustable Clasp
• San Martin Hexagon Logo

Water Resistance

• 30Bar / 300 Meters

Weight

• Approximately 163g

Warranty

• 2 Years

Why Choose the San Martin SN0154G?

The San Martin SN0154G is designed for watch enthusiasts who want a traditional mechanical diver with modern specifications and versatile proportions.

Rather than relying on an oversized case to create a strong wrist presence, the SN0154G keeps things balanced with a 40mm stainless steel case and 48mm lug-to-lug dimension.

At the same time, it delivers the specifications enthusiasts expect from a serious dive watch:

• ST2130 automatic mechanical movement
• Versatile 40mm case
• 316L solid stainless steel construction
• 300M water resistance
• Sapphire crystal with AR coating
• 120-click ceramic dive bezel
• Enamel blue, black and green dial options
• GS-crafted hands
• BGW-X1 blue lume
• Solid stainless steel bracelet
• On-The-Fly adjustable clasp
• 2-year warranty

This combination makes the SN0154G suitable for collectors looking for a watch that can move easily between everyday wear and more demanding outdoor environments.

A 40mm Automatic Diver Built for Everyday Adventure

A good dive watch doesn't have to spend its entire life underwater.

For many enthusiasts, the best mechanical diver is one that provides professional-level durability while remaining comfortable and versatile enough to wear every day.

That's where the San Martin SN0154G 40mm Diver Watch fits in.

Its ST2130 automatic movement, 300M water resistance, sapphire crystal, ceramic bezel, stainless steel construction, and BGW-X1 lume provide the functionality expected from a modern mechanical dive watch.

Meanwhile, the 40mm dimensions, three enamel dial colors, refined GS-crafted hands, and upgraded OTF clasp make it equally suitable for everyday use.

Whether you choose Enamel Black for a timeless look, Enamel Blue for a classic maritime character, or Enamel Green for something more distinctive, the SN0154G delivers a balanced combination of dive-watch capability, mechanical engineering, and everyday style.