Blancpain has dedicated its last few releases to its Fifty Fathoms Bathyscaphe editions, so it was only right for the Swiss maker’s next offering to focus on another of its great models: the brand’s original combat diver.

For Baselworld 2017, Blancpain has introduced a tribute to its Fifty Fathoms Mil-Spec 1 watch, a model that went on to help Blancpain create combat divers to serve the United States Navy.

One feature that was so important to the first-ever Mil-Spec that first appeared in 1957 is carried over into the new edition: the humidity indicator located at the 6 o’clock, which will change from white to orange if the watch’s structural integrity has been compromised.

While it is highly unlikely that this feature will be used– thanks to a half-century of advancements in seal integrity– it is nice to see the company maintain the tradition, and reference its own history.

Powering the 40mm Fifty Fathoms Mil-Spec is Blancpain’s Caliber 1150 movement. It offers a four-day power reserve, and is slimmer than the movement found in the popular Bathyscaphe model.

Blancpain will make 500 examples of its Tribute to Fifty Fathoms Mil-Spec timepiece, which will be paired with a NATO strap, a rubber-backed sailcloth strap, or a stainless steel bracelet. Pricing for the watch starts at $14,100.