This Omega http://www.speedroc.com/replica-omega-seamaster-300m-chronograph.html is a true oddity. Look at this thing. It is quite possibly the ugliest watch we have ever featured on Hodinkee. But, this is one ugly watch that deserves our attention. It is an replica omega Speedmaster Broad Arrow GMT , short for Plongeuer Professionnel, or Professional Diver in French. This watch, actually known for being not the best looking in Omega's lineup, was released in 1968 in a limited run aimed at the most intense of divers. This watch was developed with oil research firm Comex (think Rolex), and a man by the name of Jacques Cousteau. Considered to be 'super water resistant', this watch was the predecessor, and inspiration for the Rolex Sea Dweller. This replica omega Speedmaster Broad Arrow watch is a massive 45mm, especially for a 30 year old watch. It is considered new old stock, in that it has really never been worn since new. This watch was just cleaned and features all original everything. What we love about this watch is that Omega makes no bones about it being ugly (take a look at the original ad campaign to the right). Its ugliness does have a purpose, as it was the only watch able to withstand depths of 600m until the Sea Dweller came along. Take a look at what the development team put this watch through: The cases were routinely hydrostatically tested to 60ATM and shock tested (500g weight dropped onto a running watch from 25cm). In one test the watch was taken down to 1370m using hydrostatic pressure and it was reported that it only stopped at that 'depth' as the crystal had deformed to the extent that it was resting on the seconds hand, so stopping the watch from running. Interestingly, this failure can be partially attributed to the design of the case sealing, which whilst superior for the advertised 600m rating, would not be correctly designed if going beyond 1370m. What is interesting is that a perceived problem with helium infiltration led Comex to pursue development of a super water resistant watch with Rolex, eventually leading to Sea Dweller (which was rated to 610m, 10m deeper than the PloProf, what jerks they are at Rolex). However, it was later proven that the PloProf was more watertight than a submarine. This watch was extremely popular with professional divers, but its retail price was double the price of the Rolex Submariner, and thusly never gained acceptance with leisurely divers. Because of this, these watches are very rare and definitely represents a unique opportunity to own a great piece of diving watch history. It is being offered for $9950, which we think is fair.