The Omega Seamaster Aqua Terra (Reference 2502.50.00) is a classic, highly versatile timepiece from the first generation of the Aqua Terra lineup launched in the early 2000s. Often called the "Big Size" model, it is celebrated for its perfect balance of dressy elegance and everyday sporty durability.

• The Dial: Unlike later generations that feature the "teak" horizontal or vertical deck lines, this first-generation model has a clean, minimalist lacquered black dial. It features a date window at the 3 o'clock position and highly polished triangular hour markers with matching broad-arrow hands.

• The Case: It uses Omega’s iconic "lyre" twisted lugs that curve smoothly along the wrist. Despite its 42mm size, its slim 11mm thickness allows it to easily slide under a tight shirt cuff. 

• The Co-Axial Movement: It is powered by the Omega Caliber 2500. This was a revolutionary movement for Omega, featuring George Daniels' Co-Axial escapement which reduces friction, provides higher shock resistance, and extends time between required servicing. It is officially certified as a COSC Chronometer for high-accuracy timekeeping. 

• The Bracelet: Usually paired with a three-link stainless steel bracelet with a hidden sliding deployment clasp. It is also occasionally found on a factory black leather strap.
  
  

• FeatureSpecificationReference Number2502.50.00 (frequently shortened to 2502.50)

• Case Diameter42.2 mm (excluding the crown)

• Case ThicknessSlim 11.0 mm profileLug-to-Lug / Lug Width50.2 mm length / 22 mm strap width

• Case MaterialBrushed and polished Stainless Steel

• DialGlossy, non-textured black with applied arrowhead markers

• MovementOmega Caliber 2500 (Self-winding Automatic)Power Reserve48 hours

• Water Resistance150 meters (15 bar / 500 feet)

• CrystalDomed scratch-resistant sapphire crystalCase BackExhibition/Transparent sapphire display back