🔹 Overview
The RL Deepsea 44 mm Ref. 136660-0004 is one of the most formidable dive watches ever created, engineered to conquer the ocean’s most extreme depths. Built with RL’s patented Ringlock System, this professional-grade instrument withstands pressures up to 3,900 meters (12,800 feet), far beyond the limits of conventional dive watches. With its robust Oystersteel case, titanium caseback, and Cerachrom bezel, the Deepsea is the ultimate fusion of innovation, strength, and precision.

💎 Key Specifications
Reference: 136660-0004
Case: 44 mm Oystersteel with grade-5 titanium caseback
Bezel: Unidirectional rotatable bezel, black Cerachrom insert with platinum-coated numerals
Dial: Black dial with Chromalight luminescent display, 18 ct white gold hour markers and Mercedes-style hands
Crystal: 5.5 mm domed scratch-resistant sapphire (no Cyclops lens)
Bracelet: Oyster bracelet in Oystersteel with Oysterlock clasp, Glidelock extension, and Fliplock link
Movement: RL Calibre 3235, self-winding
Functions: Central hours, minutes, seconds; date at 3 o’clock with rapid setting; stop-seconds for precise adjustment
Power Reserve: ~70 hours
Water Resistance: 3,900 m / 12,800 ft, helium escape valve, Triplock crown
Certification: Superlative Chronometer (COSC + RL after casing)

⏱️ Movement
Type: Perpetual, mechanical, self-winding
Caliber: RL Calibre 3235 Manufacture RL
Features: Chronergy escapement for efficiency, blue Parachrom hairspring for magnetic and shock resistance, Paraflex shock absorbers, rapid-set date, stop-seconds
Accuracy: −2/+2 seconds per day after casing (Superlative Chronometer)
Power Reserve: Approximately 70 hours
Frequency: 28,800 vibrations/hour; 31 jewels

✅ Conclusion
The RL Deepsea Black Dial Ref. 136660-0004 is a watch without compromise — a tool engineered for professional divers yet refined for everyday wear. Its Ringlock System ensures unmatched water resistance, while the Chromalight display guarantees legibility even in pitch darkness. With the advanced Calibre 3235 at its core, it blends rugged endurance with high horology precision. Whether strapped over a wetsuit or worn with a suit, the Deepsea is a statement of ambition, resilience, and mastery over the ocean’s extremes.