Interesting X-33 prototype on the 'bay...

You're very welcome Cayohuesovespa. This is probably the rarest X-33 on the planet, and since another one has finally come up for sale after all these years it's re-ignited this thread a little. All I can say is that it'll be interesting to see how long it lasts. I myself have been rather tempted, but feel that if I gave in that'd be total greed on my part and taking away the opportunity for someone else to cherish and enjoy it. They are very comfortable and practical watches to wear too, and who knows, maybe a tiny community of prototype owners will gather here. I kinda really hope so - as there are 150 out there in the world roughly and I'd love to see more pics of others and know their stories.

For posterity, here's the description from Chrono24:

OMEGA Speedmaster « X-33 » Professional - this prototype number 48 out of 50 pces only was made by OMEGA during the test period of the X-33 digital/analog module in 1995 and 1996. These 50 prototypes were given to jet fighter pilots and also NASA astronauts to test the various functions of the digital/analog module and the reliability of the watch under high G-force. The case of the prototypes is based on the Seamaster Pro Diver titanium case from the same period, with four special push buttons to use the various functions of the watch. The special case back is covered by a kind of soundboard to enhance the sound of the different alarms featured with the functions of the digital/analog movement. The digital functions are similar to the functions found on the final watch released in 1997 in the market: Time, UTC time, Alarm, Mission Elapsed Time, etc…. This prototype was tested by a retired US Army jet fighter pilot in Arizona who participated in the test program of the Speedmaster X-33 watch set up by OMEGA. This fighter pilot used to fly vintage F-5E Tiger from a jet fighter club in Arizona. The hands are slightly different from the final version launched in 1997 (see the hour hand red rectangle) and the inner ring dial looks similar to the final 1997 model but it has tritium hour markers whereas the final 1997 model was one of the first OMEGA watch to have Superluminova hour markers. The case is definitely different as this prototype features a Seamaster case with four round push buttons and fixed 60 minutes bezel ring, whereas the final 1997 model featured a titanium case closer in design to the Speedmaster models, along with square polished push buttons and turning bezel ring. The prototype is equipped with a « kevlar » style fabric strap with rubber lining, and pin buckle. Delivered with a period OMEGA box. New battery changed in February 2021. This is a high collectible item

There is a Gen 2 alleged prototype currently on Chrono24.
Odd there would have been a run of 50 prototypes of an existing watch with only a few incremental changes made to it.
A few conspicuously absent caseback screws... was it's service history really that careless?
Interesting!

Yes I've had some chats privately about this one. There doesn't seem to be any real info from the seller either. The original prototypes that look more like mine were made in batches of 3 lots of 50 (mine is third and final batch). One thing that is interesting about that particular watch on Chrono24 is that the movement inside is a 1666C - which IS a prototype movement. So the best theory we came up with was that this was one of the original 150 but was re-cased at some point into a gen 2 midcase - a real shame if that's what happened, as to my mind the prototype case is the better design (well unless you have astronaut gloves on perhaps).

Hmm not only would it be a shame, it would be almost inexplicable... would be a considerable amount of effort to source a Gen 2 case, swap it, then after all that retain the original caseback anyway? Not to say it's impossible but seems highly improbable... then again stranger things have certainly happened!

More likely that either the case was smashed and Omega replaced it, or if it was within an organisation (like the military) then a supply person ordered a new case and it was fitted in house (maybe losing the screws into the bargain). You couldn't order a replacement prototype case from Omega. The only way to verify any of this speculation would be through Omega - but they don't give away much. It is a weird one, and not one I'd gamble on myself. The more expensive good one on Chrono with the red hour hand was snapped up not long ago - a much better buy - though pricey. Now we'll probably wait another 5 or 6 or 10 years to see another... Be interesting to see the price as they're going up, albeit slowly, as with only 150 made (and those were the ones released to the testers, I mean), there's not a lot to compare too. Certainly rarer than a Snoopy though!

Indeed. It is interesting that there's no serial number stamped on the lug where it's usually found... on one hand this makes it appear more like a prototype, on the other hand makes it pretty much impossible to cross-reference using Omega's archive service. IMO it would be worth risking the gamble for a small premium but the 7k-8k€ difference in markup is a lot to lose.