The Vostok-Europe Energia-2 Automatic Professional dive watch, model NH35A/575C649, is a high-performance timepiece that skillfully balances functionality with a striking design. Its features are carefully tailored for both professional divers and watch enthusiasts who appreciate robust and distinctive watches. Key aspects of this watch include:

1. Design and Size: With a diameter of 48mm and a thickness of 17.3mm, the watch makes a bold statement on the wrist. Its substantial size ensures easy readability and adds a commanding presence.

2. Material and Coating: The watch is constructed from 316L stainless steel, which is known for its excellent resistance to corrosion, particularly important in a diving watch. This durability is further enhanced by a black PVD (Physical Vapor Deposition) coating, providing a sleek look while also increasing scratch resistance.

3. Helium Release Valve: A critical feature for deep-sea diving, the helium release valve allows the watch to safely release helium gas that may enter the watch during prolonged underwater excursions. This feature is essential to prevent damage during decompression phases of diving.

4. Crown: The screw-down crown contributes significantly to the watch's water resistance, preventing water from entering the case during dives.

5. Crystal: Equipped with a 3.5mm thick K1 crystal, the watch offers a unique balance between scratch resistance and shatterproof qualities. K1 crystal is tougher than standard mineral glass and less prone to shattering than sapphire crystal, making it well-suited for the rigors of diving and everyday wear.

6. Tritium Illumination: The watch features tritium illumination on its hands and dial. Tritium, a self-luminous material, provides consistent illumination without the need for recharging from light sources. This makes the watch highly readable in low-light conditions and underwater.

7. Water Resistance: With a rating of 300 meters water resistance, this watch is suitable for professional diving, ensuring it can withstand significant depths and pressures.

8. Straps and Accessories: The watch comes with both a leather strap and a silicon strap, offering versatility for different styles or activities. Additionally, the included strap-changing tool allows for easy customization depending on the wearer’s preference.

9. Packaging: It is presented in a professional dry box capable of holding up to four watches. This not only makes for an impressive unboxing experience but also serves as a practical storage solution for watch enthusiasts.

10. Dial: One of the most striking features is the full-lumed green dial, which not only adds a vibrant aesthetic but also enhances visibility in dark conditions.

The Vostok-Europe Energia-2 Automatic Professional dive watch NH35A/575C649 is an exemplary combination of robust functionality and distinctive style, making it a highly desirable piece for both diving professionals and watch collectors.