Hamilton has always been associated with its military roots. Their timepieces have been tried-and-tested in the toughest conditions on land, air, and sea, producing watches of the highest performance standards has become second nature to them. Many of Hamilton's watches continue to be influenced by their proud heritage, upholding the value of producing robust watches with high quality and precision.

Combining historic military design with modern upgrades, the Hamilton Khaki Field King Auto Black Ref. H64455533 is well respected by many watch collectors and enthusiasts for its excellent specifications, versatility and great value for money. The brushed stainless steel case features a 40mm diameter and a lug to lug distance of 49.7mm; these dimensions give the watch a comfortable fit that will cater to many wrist sizes. In contrast to the brushed finishing on the case, the bezel is done in a high polish finish, exerting a sporty vibe, making this piece fit right in place even in dressier settings—moreover, the Khaki Field King Auto Black Ref. H64455533 has a lug width of 20mm, which allows for a wide combination of straps. The watch comes fitted with a rustic brown leather strap paired with a steel buckle engraved with the Hamilton logo. Overall, the case feels sturdy and well built - just what a military-inspired watch should feel like.

Being a tribute to military issued watches, the dial of the Khaki Field King Auto Black Ref. H64455533 closely resembles the Hamilton Military Issue MIL-W-46374, consisting of white printed Arabic numerals and an inner ring with military time which were essential for military timing operations. Against the black utilitarian dial, the syringe-shaped minute and hour hands makes the dial incredibly easy to read, explicitly designed for the hour hand to touch the inner indices for 24-hour military time while the minute hand reaches the outer minute markers. The hands and indexes are treated with Superluminova luminous paint for a bright green glow in the dark, serving as a modern replacement for the radioactive tritium lume used on military issued watches.

The dial of the Khaki Field King Auto Black Ref. H64455533 is evidently built for purpose, being uncluttered and legible. One of the new additions to the traditional mil-spec dial includes the date and day complication - cleverly situated at the 12 o’clock position, retaining the dial's legibility and symmetry. Protecting the dial is a piece of slightly domed sapphire crystal, providing superior scratch resistance.

At the heart of the watch lies the Hamilton caliber H-40 automatic movement, which is a modified 25 jewel ETA day/date movement. The movement's main highlights include the boosted 80-hour power reserve achieved by lowering the 4 Hz beat rate of 28,800 beats per hour to 3 Hz (21,600 beats per hour). The lowered beat rate also translates to a more robust movement due to the lesser friction produced between the parts over time. The movement is operated by the knurled crown at the 3 o’clock position, protected by crown guards against accidental knocks that may harm the movement. At the back of the watch, the movement is viewable through the see-through exhibition case back, featuring a custom decorated rotor with the Hamilton logo engraved. The case back is screwed in to attain a water resistance of 5 bar (50 meters).

All things considered, the Khaki Field King Auto Black Ref. H64455533 truly became a cult favorite, bringing great specifications while retaining many of its military heritage designs. At this price point, obtaining an automatic Swiss-made timepiece with a prestigious history would not be an easy task. With this piece's practicality and versatility, we can see why this piece reigns as the ‘king’.