12-hour GMT bezel insert, used on US issue navigator and dive watches for more than a generation this insert type can be used to time short intervals such as decompression stops and tracking a second time zone.

Mk II Sea Fighter Type II C day/date (Swiss Made)

Details:
Movement: ETA 2836-2 (Elabore grade/Rhodium plated), Incabloc shock protection, hack setting, automatic with manual winding capability.
Crystal: Double domed sapphire crystal
Luminous: SuperLumiNova rated to glow on a full charge for a minimum of 7 hours
Water resistance: 20 ATMs (200 meters)
Case Finish: Mirror polished 316L stainless steel
Bezel: 120 click unidirectional bezel (Several bezel and bezel insert styles will be available.)
Strap: natural rubber strap
Crown: Double gasket screw-down crown
Other: Drilled through lugs for ease of strap removal.
Regulated in 6 positions for optimal time keeping performance
Travel case and strap changing tool kit

Dimensions:    
Case Width: 42.35 mm (without crown)
Case Thickness: 14.22 mm
Case length: 48.90 mm end to end
Lug width: 22.0 mm
Weight: 99 grams