A Navy SEAL ranked five dive watches. The $0 one won.

The score is one Navy SEAL's ranking of five watches, so weigh it as an opinion. The specs are not opinion. The table above lists depth rating, crystal, power, strap system and price for all five watches, from each maker's published specifications and US prices. Check them. The Trident 300 matches the Rolex on depth rating and crystal, beats the Casio and the Seiko on both, is the only one of the five with nothing to charge, wind or replace, and costs today.

It carries a 300M (30 ATM / 1000 ft) rating, which Ironway lists as a professional dive rating, with a unidirectional 60-minute bezel, luminous hands and markers, and a sapphire crystal. A watch rating is a static pressure test, not a depth you can swim to: 5 ATM is rain and splash, 10 ATM is swimming, and the ISO 6425 dive watch standard sets 20 ATM (200 m) as the minimum for scuba. At 30 ATM the Trident 300 clears that with margin. Have it pressure-checked by a dive shop if you depend on it for working dives, as you would with any watch.

Solar-Powered Japanese Quartz. Not an automatic. That is deliberate: quartz keeps better time than a mechanical movement at this price, solar means you never open the caseback for a battery, and unlike an automatic it does not stop when you leave it in a drawer for a few days.

No. Hours, minutes and seconds only. Many divers expect a date window, so we say it plainly here. The upside is a cleaner dial and one less thing to set after a flight.

The Casio MDV-10 is a reliable watch for under $100, and it scored a 7 in the ranking. The differences are checkable: the Trident 300 is rated to 300 m instead of 50 m, has a sapphire crystal instead of mineral glass, runs on solar power instead of a battery you replace, and swaps between a rubber strap and a steel bracelet on the same 24mm lugs. If those four things do not matter to you, the Casio is a fine watch.

The case is 46mm (1.81 in) across and 16mm (0.63 in) thick, the largest watch Ironway makes. The strap is 24mm wide and 260mm (10.2 in) long. It is a full-size diver with real presence. If you prefer a smaller watch, Ironway's Field Watch 38 or 41 will suit you better.

Shipping is free on every order, with a tracking link by email. Orders are prepared in 1 to 3 business days and delivery to the USA and Canada takes 5 to 9 business days after that. You have 30 days from the date you receive your watch to initiate a return; it must be unused and in its original packaging, and return shipping is not covered by Ironway. The movement, hands and dial are covered by a 2-year international warranty. Questions go to support@ironway.com.