Black Open Heart - NAUTIKO

The APEX Black Open‑Heart delivers a clean, modern, and mechanically expressive design. The deep matte‑black dial paired with a polished stainless‑steel case creates a sharp, minimalist aesthetic that feels refined, confident, and unmistakably APEX. The open‑heart window reveals the beating NH38 movement beneath, adding depth and character to an otherwise stealthy, monochrome dial.

With a 41mm case size and a slim 12mm thickness, the Black Open‑Heart wears comfortably on any wrist. Bright C3 lume on the hands ensures visibility in low‑light conditions, while the screw‑down crown, solid case back, and 3 bar water resistance provide practical durability for everyday use.

Hand‑assembled with precision, the Black Open‑Heart feels solid, reliable, and ready for anything.

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Key Features

• 41mm case size — bold, modern proportions with strong wrist presence
• 12mm thickness — slim, comfortable, and ideal for daily wear
• Open‑heart dial — showcases the mechanical heartbeat of the NH38 movement
• C3 lume — bright, long‑lasting glow for maximum visibility
• Screw‑down crown — added security and improved moisture resistance
• Solid case back — clean, durable, and built for long‑term reliability
• 3 bar water resistance — protection from everyday splashes and light exposure
• Matte‑black dial with stainless‑steel case — clean, modern, and versatile
• Reliable NH38 Seiko movement — open‑heart, no‑date, trusted accuracy, and easy servicing
• Hand‑assembled — each piece built with care and attention to detail
• Stainless steel finish — durable, refined, and built to last

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Who It’s For

The Black Open‑Heart is perfect for enthusiasts who want a watch that’s:

• Clean, modern, and versatile
• Minimalist with mechanical character
• Comfortable for everyday wear
• Highly legible in all conditions
• A confident, understated piece with a premium monochrome identity