Helm Miyako

The Helm Miyako Stainless Steel watch is a purpose-built dive watch that blends rugged durability with utilitarian aesthetics. Designed to meet professional diving standards while retaining comfort and wearability, the Miyako delivers uncompromising performance and build quality. Below are the detailed technical specifications:

Case and Bezel
- Material: 316L stainless steel case with brushed finish for corrosion resistance and tool-watch styling  
- Case Diameter: 40mm (excluding crown)  
- Thickness: 13.8mm  
- Lug-to-Lug Length: 48mm  
- Bezel: Unidirectional 120-click rotating bezel with a fully lumed ceramic insert and engraved dive time scale  
- Crown: Screw-down crown located at 4 o’clock, reducing wrist interference while maintaining a secure seal

Dial and Crystal
- Dial Color: Matte black (varies by version) with high-contrast white markers for superior underwater visibility  
- Markers: Applied indices filled with BGW9 Super-LumiNova for long-lasting luminescence  
- Hands: Broad sword-style hands with BGW9 Super-LumiNova coating for excellent legibility in low light  
- Crystal: Flat sapphire crystal with internal anti-reflective coating for scratch resistance and enhanced clarity

Movement
- Caliber: Seiko NH35  
- Type: Automatic mechanical movement with manual winding and hacking seconds  
- Power Reserve: ~41 hours  
- Frequency: 21,600 bph (3 Hz)  
- Jewels: 24  
- Accuracy: -20 to +40 seconds per day

Bracelet and Clasp
- Bracelet Material: 316L stainless steel with brushed finish and solid end links  
- Width: 20mm at lugs, tapering to 18mm  
- Clasp: Milled stainless steel fold-over clasp with double push-button release, safety lock, and 6-position micro-adjustments

Water Resistance
- Rating: 300 meters / 1,000 feet  
- Standard: ISO 6425 certified for professional diving  
- Case Back: Screw-down stainless steel case back engraved with model details  
- Gaskets: High-grade Viton® and Tefzel® gaskets for enhanced water and chemical resistance

Additional Features
- Lume: BGW9 Super-LumiNova on dial, hands, and bezel for all-angle visibility  
- Anti-Magnetic Resistance:** 4,800 A/m  
- Shock Resistance:** Designed to withstand harsh impact and vibration  
- Helm Quality Control:** Pressure-tested and inspected individually before shipment

The **Helm Miyako Stainless Steel** is a compact yet tough dive watch designed for real-world performance. With its ISO certification, top-tier materials, and tool-watch design ethos, it’s an ideal choice for divers, adventurers, and watch enthusiasts looking for reliable everyday toughness.