During the Vietnam War, the US Military contracted Benrus to design and build new dive watches, specifically for covert operations. These watches had to be stealthy, legible, and durable; Benrus delivered in spades. What they came up with was the Benrus Types I and II, military specification MIL-W-50717. These watches would go on to be worn on the wrists of CIA agents, Navy SEALS, and Green Berets throughout the Vietnam War, making the Types I and II some of the greatest US military dive watches ever made.
The watch’s minimalist and basic design exemplifies “form following function”. A robust, automatic 17 jewel modified ETA 2620 movement is housed in a 40mm, bead-blasted, one piece steel case, and topped with a 3mm thick acrylic crystal. Although the case was designated as “one piece”, it was actually two pieces, and featured a permanently press-fit caseback in an effort to increase water resistance. As a result, the watch was capable of reaching depths of over 1200 feet. Adding to its robust nature, the Types I and II are non-magnetic, which allowed divers to work with magnetic mines underwater. Finishing the look, Benruses were secured to the wrist with NATO straps, preventing any chance of the watch coming detached from the wearer’s wrist.
Benrus Type I (left) and Type II (right)
Over a period of roughly ten years, the US Military had four different versions of the watch commissioned. The first, and most rare, variant to be issued was the Type I Class A “Sterile”. Although all variants of the watch were technically sterile, this variant went even further, as it had no military markings. The thinking behind the sterile examples is often romanticized by collectors, who theorize in the event the wearer is captured, he would have no visible ties to US forces. In reality, it’s much more likely these examples were just prototypes – plus, the captured soldier’s uniform would likely betray his allegiance. The “Sterile” would then be followed by a version with military markings, known simply as the Type I Class A.
The great success of the Type I’s would result in Benrus being contracted to build another version of the watch, the Type II. Of the Type II variants, there was the Class A with luminous dials and hands, and Class B variants being non-luminous. These maintained the same case and bezel design, but with a different dial. Unlike the Submariner-styled dial of the Type I’s, Type II’s had triangular luminous plots at each hour, accompanied by both Arabic numerals, and 24-hour markers. On paper it might sound cluttered, but in reality it’s a highly functional and legible design.
Now, over 40 years later, the Benrus Types I and II are still prized by military watch collectors. They’re even heavily influencing modern homage watches such as the MKII Paradive and Meisturwerk Machinen MM-01. The continued influence today is just another indication that the Benrus Types I and II have made a truly lasting impact on military dive watch history.
by 
Vinny DiBiase
Boy are those watches hideous