I agree its not a 240 cal in fact the movement is a spare movement I use for testing. However I wanted to be able to put something in an egi other than the standard Unitas and thought why not show it off a little with a display case back.

The project isnt yet complete but with a simple change of the Case Back and a Brass movement ring it makes the watch that more interesting to look at... Also I havent polished the Case Back I perfer it to match the rest of the watch (it always seemed a bit odd having a brush steel case and polished case back)