Omega, as a quality brand and image carrier, was placed more 'up-market' while Tissot aimed for the somewhat less expensive segment. Below are two examples of Tissot 33.3 chronographs in chromium-plated case. Including Lémania (designer/ producer of the 15TL resp. 33.3 movement) all three brands used the same caliber in their chronographs, albeit in slightly different form of optical finish.
Production of Omega's very reliable 26.5 movement was indeed handed over, early-on and in great numbers, to Tissot's factory in Le Locle. Small wonder that they based their 27.53 caliber on this succesful and sturdy Omega design - even including an indirect central-seconds version like your example. Omega off course had shown the way already some years before with the caliber 23.4 and it's 23.4SC derivative.
Thanks for showing,
Best, Ben.


