I picked this thing up at a watch fair for £260 and can't believe how snazzy it is. It's based on a manually-wound Swiss alarm movement (A Schild 1475, in this case it's a Citizen 3102). There's a pin in the reverse of the case that the alarm hammer strikes, so the whole thing vibrates as well as rings. There's a stud on the case so you can only press the back on in one way. Here's the hammer doing its thing, obviously with the case back off... With its dauphine hands and sunburst finish on the dial, it's a great looking watch ... ... and at 41mm case but still manually wound, it's relatively thin. I know we all love Omega, but when stuff like this is available at 1/10th or less of the price of a similarly-aged watch from Bienne, sometimes I think there's more fun to be had elsewhere.