The Universal Geneve 884100/02 is powered by a Universal Geneve Caliber 125, which is a modified Valjoux 23 (VZ). The Valjoux 23 was workhorse manufactured from 1914 to 1974, manually-wound with 18,000 vpm and a 48 hour power reserve, with the characteristic of the pusher at 2 o’clock being slightly closer to the crown than the pusher at 4 o’clock. I believe this caliber was exclusive to the Universal Geneve Uni-Compax line (as with everything on this site…please do let me know if this isn’t accurate).
There are few Universal Geneve 884100/02 seen in total, and just a handful with movement images.
Of movement images seen, all are stamped on the distinctive U-shaped chronograph bridge:
UNIVERSAL GENEVE
SWISS
125
At the edge of the train wheel bridge is stamped:
17 SEVENTEEN JEWELS UNADJUSTED
I have not seen any pieces with import codes stamped on the movement, though with so few movements seen, this isn’t surprising. I don’t believe it would be unusual to see some of the pieces (known or unknown) with codes.
One difference seen is in the movement plate stamp. Some have 23 and the Valjoux symbol (“R”), and others have these machined off entirely (see below), seemingly so Universal Geneve could market this as a Caliber 125, as opposed to a the modified Valjoux 23 that it is. Based on serial numbers, though few, I have not yet been able to establish a pattern of when the Valjoux stamping was removed.
