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Differs

Longines Spirit Zulu TimeL3.812.4.53

Longines Spirit FlybackL3.821.4.53

Shape: Round; Not known; Round
Diameter: 42 mm; 42 mm; 42 mm
Thickness (differs): 14.1 mm; 15.25 mm; 17 mm
Lug to lug (differs): 49.4 mm; Not known; 49.5 mm
Lug width (differs): 22 mm; 20 mm; 22 mm
Material: Stainless steel; Stainless steel; Stainless steel
Bezel: Bidirectional rotating; Bidirectional rotating; Bidirectional rotating
Caseback (differs): Solid; Screw-down; Display (sapphire)
Crystal (differs): Sapphire, Anti-reflective on both sides; Sapphire, Domed, Anti-reflective on both sides; Sapphire, Anti-reflective on both sides
Crown (differs): Screw-down; Push-pull; Screw-down
Water resistance: 100 m; 100 m; 100 m
Weight (differs): 112.9 g; Not known; 127.7 g

Calibre (differs): Longines L844.4; Breitling Gallet 23; Longines L791.4
Type: Automatic; Automatic; Automatic
Power reserve (differs): 72 h; 65 h; 68 h
Frequency (differs): 25,200 vph (3.5 Hz); 28,800 vph (4 Hz); 28,800 vph (4 Hz)
Jewels (differs): 21; Not known; 28
Certification: COSC; Not known; COSC
Functions (differs): Hours, minutes, seconds and date. 24 hours hand with time zone mechanism; Not known; Hours, minutes, small seconds at 9 o'clock
Chronograph mechanism: central 60 seconds hand and 30 minutes counter at 3 o'clock
Complications (differs): Date
GMT / second time zone; Chronograph; Chronograph
Flyback chronograph
Small seconds

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