In the civilian world, the most common timekeeping system is the 12-hour dial, which shows the same time twice a day. Therefore, two similar notations should be distinguished by different notations: AM and PM. This makes it easy to confuse timeframes.

In the military arena, confusion about the meaning of time can be deadly. Therefore, the military had to improvise a timing system that would reduce the possibility of ambiguity. This introduced the military time system, also known as the 24-hour clock system.

Soldiers often used devices for long-range communication to enhance their cohesion, offensive, and defensive strategies. A slight error in information can lead to wrong actions. This was one of the drawbacks of the 12-hour clock. For instance, in the 12-hour system, it is very easy to confuse 12 midnight and 12 noon. It is also very difficult in to do swift calculations in time difference. For example, in the 12-hour system, it is harder to know that something lasts for six-hour when told it starts from 10:45 to 4:45. On the contrary, it is easier to comprehend that it starts from 10:45 to 16:45. For these challenges in the 12-hour system, the US Navy adopted the 24-hour system in 1920 which was later adopted by the US Army in 1942. However, the 24-hour clock was used informally by the Army and Navy in the latter half of World War I. Evidence of this can be found on the few dials of World War I American trench clocks.

The 12-hour clock is still widely used in the United States today. The 24-hour system is also popular with airlines and other transit agencies where mistiming can cause confusion. Pilots, scientists and polar explorers employ his 24-hour clock. This is most likely due to the sun shining or being dark in that location for a long period of time. Night, which takes up most of the day, can be confusing for explorers. Professionals with highly sensitive operations, such as hospitals and intensive care units, also provide care around the clock. A small mistake in drug administration can lead to patient death.

While the world adapts, adapts, and optimizes its systems to meet the needs of new technologies and methods, the history of the military era continues to be written.

The Steeldive VH60 SF746 is a state-of-the-art instrument for professional pilots, designed for reliability and accuracy to meet current aviation specifications, with a 39 mm diameter dial for enhanced legibility. Subtle but significant design evolutions in the case, bezel, lugs and dial make the 39mm Steel Dive VH60 SF746 a modern pilot's watch rather than a remake of the original. Strictly in its original black and white paint scheme and without the patina that often twists the perception of historic watches.

Watch Specification
Model: SF746
Movement type: Sweep second quartz movement
Movement model: VH60
Battery model: SR920SW（2 years)
Case material: 316L stainless steel
Case back: 316L stainless steel
Watch mirror: flat sapphire crystal with AR coating.
Water resistance: 200m / 20 ATM
Luminous: Swiss C3 green and BGW9 blue super luminous.
Crown: Screwdown Crown
Case back: Screwback Case
Clasp: 3 inner hold adjustable clasp
Watch Dimension
Case diameter:39mm ( without crown)
Case length: 49mm (lug to lug)
Case thickness: 12mm 
Lug width: 20mm