SKU Code: GMT/SS/SILB/QZ

This GMT dual time zone watch in a stainless steel finish is one of our most popular models, featuring a high-performance quartz Ronda 515.24 movement, an anti-reflective and impact-resistant sapphire crystal, and a scratch-resistant ceramic bezel. The robust 300m / 1000ft water-resistant steel casing makes it ideal for swimming, snorkeling, and water sports. However, since the bezel is designed for tracking time across two time zones, its suitability for diving applications is somewhat limited. That said, from a water-resistance perspective, the watch is fully capable of handling underwater environments.

The Concept of a GMT Watch

The idea behind GMT watches is both clever and straightforward. Unlike conventional watches, where the hour hand completes a 12-hour rotation, a GMT watch adds a second hour hand that completes a 24-hour rotation. This hand is paired with a 24-hour scale on the bezel, allowing the wearer to track a second time zone with ease.

GMT watches often resemble diver watches at first glance, but their functionality is distinct. The 24-hour hand moves once per day instead of twice, eliminating any confusion between AM and PM.

Designed for Pilots

We originally produced these watches for long-haul airline pilots and military transport pilots, including those flying aircraft like the Lockheed C-130 Hercules and Airbus A400M. The GMT functionality allows them to track both departure and destination time zones at a glance.

Dimensions and Specifications

• Water Resistance: 300m / 1000ft
• Movement: Ronda 515.24 Quartz
• Case Material: Stainless Steel
• Bezel: Scratch-Resistant Ceramic
• Crown: Screw-down
• Case Width: 45mm (including crown) / 40mm (excluding crown)
• Thickness: 15mm
• Crystal: Sapphire with Anti-Reflective Coating
• Crystal Diameter: 31mm
• Lug-to-Lug: 49mm
• Straps Included: Silicon Strap + Two 20mm NATO Webbing Straps (One Black, One Grey)

Understanding the Benefits of Sapphire Crystal

Many customers ask us about the advantages of sapphire crystal compared to standard mineral glass. The key benefits include:

• Superior Strength: Sapphire crystal is extremely strong and highly resistant to shattering and scratches.
• Ideal for Active Lifestyles: These qualities make it the preferred choice for military personnel, security forces, police officers, and outdoor enthusiasts—a group that makes up over 70% of our customer base.
• Exceptional Durability: From our experience, over 90% of watch crystal cracks occur in watches with mineral glass, even when hardened. Sapphire is significantly more durable in harsh conditions.
• Heat Treatment Process: After manufacturing, sapphire glass undergoes heat treatment to remove internal stresses, further enhancing its durability. Two anti-reflective coatings are also applied.
• Used in High-End Devices: Sapphire crystal is now even used in high-end smartphones, such as the latest iPhones.

Of course, sapphire crystal comes at a higher cost, which is why it is typically found only in premium timepieces. However, for those who demand long-term durability and clarity, the investment is well worth it.

For more details on how the Ronda 515.24 GMT movement operates, please refer to the official manual:
🔗 Ronda 515.24 GMT Movement Guide