The Longines HydroConquest L3.788.4.70.6 is a premium Swiss dive watch that received a major, highly praised redesign in March 2026. This iteration swaps out the traditional oversized Arabic numerals for an elegant, vintage-inspired geometric dial layout while maintaining its signature rugged tool-watch performance.

• Streamlined Proportions: Despite its 300m depth capability, the case profile remains remarkably slim at 11.70 mm, allowing it to easily slip beneath shirt cuffs. The updated lug shape and less aggressive crown guards prevent the watch from overhanging smaller wrists.

• Dial Aesthetic: The prominent Arabic numerals from previous models have been replaced with geometric applied markers—circles at 6 and 9, a triangle at 12, and batons elsewhere—hearkening back to the classic 1990s Longines Admiral series. 

• Advanced Balance Spring: The inclusion of a monocrystalline silicon balance spring significantly enhances resistance to magnetic fields and temperature shifts, keeping its time tracking stable. 

• Premium Bezel & Clasp: The 120-click ceramic bezel provides incredibly sharp, crisp feedback. Depending on configuration, it comes either on a classic H-link steel bracelet or a sleek Milanese mesh bracelet, both fitted with double security folding clasps and on-the-fly micro-adjustments.

• Case Size: 42.00 mm diameter | 11.70 mm thickness | 51.20 mm lug-to-lug distance.

• Movement: Longines Caliber L888 (specifically L888.5, built exclusively for Longines by ETA).

• Power Reserve: Up to 72 hours.

• Frequency: 25,200 vibrations per hour (vph).

• Water Resistance: 30 bar (300 meters / 1000 feet).

• Materials: 316L stainless steel case; highly scratch-resistant ceramic unidirectional rotating bezel.

• Crystal: Scratch-resistant sapphire with multiple anti-reflective layers on both sides.

• Dial Details: Deep, glossy black lacquered polished dial utilizing premium Swiss Super-LumiNova® on hands and markers.