OceanicTime, a blog specialising in dive watches and Spanish microbrand Crepas have come together to reproduce one of the most unusual and interesting military issue dive watches – the gargantuan Hydrographic Survey watch produced by Longines for the British Royal Navy in the 1940s.

With a 51mm case made of sterling silver – complete with a canteen-style crown cover attached with a chain – the Hydrographic Survey watch was made for the commando frogmen of the Royal Navy, essentially the British equivalent of Italy’s Decima Flottiglia MAS, the unit best known for wearing Panerai watches. Only a handful are known to exist today, explaining why they are almost never seen.

Made by Crepas to mark the 10th anniversary of OceanicTime, the Hydrographer 1942m is a more wearable Hydrographic Survey watch. Rated to 1942m, the case is 45mm and 15mm high. It’s made of stainless steel, and available in either a brushed, sandblasted or mirror-polished finish. Another option is the crown, which can be on the right or left of the case.

The case is fitted with a unidirectional rotating bezel that has two notches on opposite edges, just like the original, while the crown is oversized and functional, a nod to the original canteen crown. And the sapphire crystal is a thick sapphire 5.5mm high, and sits above the bezel; the case height of 15mm does not include the crystal.

Unusually, the helium escape valve is in the centre of the screw-down case back that’s been engraved with the British military “Broad arrow” symbol as well as “HS”, just like the original.

The dial is matte black and based on the original, but with wider hour markers and slightly redesigned hands.

And the movement is an ETA 2892-A2 that has been modified to remove the date function. Not only is the date mechanism removed, but the keyless works have been modified to remove the date setting position when pulling out the crown.

Price and availability 

The first 100 Hydrographer 1942m watches are priced at €699, and the price will rise for €850 for subsequent watches. Prices do not include taxes.

The Hydrographer 1942m is available direct from Crepas.