Zodiac Super Sea Wolf Pro-Diver GMT ZO3557 Men’s 42mm Black Automatic Dive Watch – Black Sunray Dial, Black Rubber Strap

Zodiac Super Sea Wolf Pro-Diver GMT ZO3557: A Black 42 mm Swiss Automatic with a Second Time Zone

The Zodiac Super Sea Wolf Pro-Diver GMT ZO3557 is a 42 mm Swiss automatic dive watch in a black steel case, with a black sunray dial, a black rubber strap and a rating of 300 metres. It combines two roles that do not often share a case: a serious diver’s tool and a travel watch that shows a second time zone. The result is a dark, purposeful watch with a 24-hour GMT hand, a rotating bezel and luminous markers, aimed at people who want a robust Swiss mechanical watch for water and for travel.

Case and Wrist Presence

The round case is 42 mm in diameter, a size that works on most wrists and keeps the watch in proportion despite its dive-watch build. It is stainless steel with a black finish; one retailer specifies solid 316L steel with a black PVD coating, and others describe a stealth black finish. A crown guard protects the screw-down crown, which carries the Zodiac logo, and the case back is also screwed down. Together these give the watch its 300 metre rating. Black cases show less glare than polished steel, and the watch reads as a low-key piece in daily wear.

• 42 mm round case in black-finished stainless steel
• Screw-down crown with crown guard
• Screw-down case back for water tightness
• Sapphire crystal over the dial, as listed by retailers

Dial and Bezel

The dial is black with a sunray finish, which means fine brushed lines radiate from the centre and catch the light as the watch moves, so the surface shifts between deep black and a soft charcoal sheen. Luminous hour markers and luminous filled hands make the time legible in the dark, and the hands are treated with Super-LumiNova according to one retailer. The outer bezel is black and rotates for timing dives and other elapsed periods. A second, inner 24-hour bezel, operated by its own crown, sits within the case and works with the GMT hand to read a second time zone.

The colour scheme is almost entirely black, with luminous detail doing the work of marking time. That keeps the watch calm to look at and puts the emphasis on legibility instead of decoration.

Automatic Movement and GMT Function

The watch uses a Swiss automatic movement, wound by the motion of your wrist, and it is described as a COSC-certified chronometer. COSC is the Swiss official chronometer testing body, and certification means the movement has passed a set of accuracy tests. Different retailers name the calibre differently, so we do not state one here. The GMT hand turns once every 24 hours, and you read it against the inner 24-hour bezel to track a second time zone while the main hands show local time.

• Swiss automatic movement, no battery required
• COSC chronometer certified for accuracy
• GMT hand and 24-hour bezel for a second time zone
• Rotating bezel for timing elapsed periods

For frequent travellers, this means you can keep home time visible while you set the main hands to local time. For divers and boaters, it means you can time an immersion and still read the hour.

Rubber Strap and Fit

The strap is black rubber, listed as a fluoroelastomer type by one retailer, 20 mm wide at the lugs, and closed with a traditional tang buckle. Rubber suits a dive watch because salt water, chlorine and sweat do not harm it, and it dries quickly. A 20 mm lug width is a standard size, so third-party straps are easy to find if you want to change the look. The strap is soft enough to be comfortable from day one and holds the watch in place during active use.

Water Resistance in Practical Terms

The ZO3557 is rated to 300 metres, ISO certified, according to most listings, with one older listing quoting 200 metres. At either figure it is a genuine dive watch, suited to swimming, snorkelling and recreational diving. For safety, make sure the crown and the second crown are fully screwed in before water contact, and do not operate either while the watch is wet. Rinse the watch with fresh water after sea use and have the seals tested at regular intervals if you dive often.

About Zodiac

Zodiac is a Swiss watch brand founded in 1882 and best known for the Sea Wolf, a dive watch it introduced in 1953. The Sea Wolf is among the earliest purpose-built modern dive watches, and the Super Sea Wolf family continues that lineage with contemporary cases, bezels and movements. The Pro-Diver GMT adds the travel function to that diving heritage.

Who This Watch Suits

• Divers and swimmers who want a mechanical watch rated well beyond the usual
• Frequent travellers who track home time and local time
• Collectors who value Swiss automatic movements and chronometer certification
• Wearers who like all-black watches with a tool-watch character
• Anyone after a 42 mm dive watch that is not oversized

Because the case is 42 mm, this watch is classed as a men’s watch under our sizing rule.

Care and Maintenance

Rinse the watch in fresh water after swimming in the sea or a chlorinated pool, and wipe it dry with a soft cloth. A black coating can wear at the edges over years of hard use, so avoid abrasive cleaners and rough surfaces. Because the movement is mechanical, plan a service by a qualified watchmaker every few years, and have the seals pressure tested if you dive. Wear it regularly to keep it wound, and keep it away from strong magnets such as speakers. If it has stopped, give the crown a few turns before setting the time.

Technical Specifications