“Mega Jumbo” does as “Jumbo” not refer to one model or brand within the watch world. It refers to a very specific type of watches. “Jumbo” timepieces are mostly time-only models that have a significantly larger size than its contemporaries from a certain era. Let’s say that in the ‘30s 28-31mm was the size of men’s watches. So, if you found one that was 34-35mm you could consider that a “Jumbo”. Though as of lately we are calling watches that are above 36mm or so for “Jumbos” but here we have a watch which was intruduced in 1950´s and it is in a size of 39 mm, it is the second largest of the Omega “Jumbo” models!
Omega released the reference 2505 in 1946. To put it into perspective during the ‘40s the average size of a wristwatch was 33-34mm. The “Jumbo” race continued with the “Mega Jumbo” models 2444 and 2445 at 39 mm and the last one was the largest, the 2808 with 40mm
The CK 2545 case is made of stainless steel with a press-in back case. The movement inside the Omega reference 2544 is the caliber 265. It is a manual wind, sub-second movement with roughly 45 hours of power reserve, 15 jewels, and 18,000 Vph. The 265/283 is also the straight descendant of Omega’s legendary workhorse caliber 30T2. That one (the 30T2 that is) also has 15 jewels but no shock protection. The 265/283 on the other hand already has that and it’s antimagnetic. Back in the day often times a watch with a larger case was the indicator that it is anti-magnetic. The movement family the 265 belongs to went into production between 1939 and 1963 during which hundreds of thousands of movements came out of Biel.
The CK 25445“Mega Jumbo” is one of the most sought after in this cathegory and the steel version with rare dials commend high prices