Polerouter collectors (and UG collectors in general) have become pretty well accustomed to referring to models by their model reference number. This is the typically 5 to 8 digit number on the case, that defines what the dial, case, crown, and movement should look like. But, have you ever wondered what they actually mean? It turns out these arent just random numbers – there’s a system behind it and a meaning for each digit.
The coding system for reference numbers of 1940s and 1950s UG chronographs have been well-documented by Pietro Giuliano Sala, in his book “Universal Watch Geneve”. This type of coding system seems to have carried over into the Polerouter range through the 1950s and 60s (and likely the rest of the UG range through this period). In 1965 UG updated their coding system, which means we can broadly divide the Polerouter era into two coding systems: (1) pre-1965; and (2) post-1965.
Pre-1965 era polerouters
Lets first take a look at the pre-1965 era for polerouters.
The first number refers to the case material:
1 = 18k gold case
2 = steel/gold-capped steel case
4 = gold-plated case
The second number set refers to the movement:
02=bumper automatic movement, time only.
03=microtor automatic movement, time only
04=microtor automatic movement, time and date
The third number set refers to the case style, where the Time-Only range used 2 digits, and the Time-Date range used 3 digits.
Time-only cases, e.g:
14 = gold capped 35.5 mm case, bombe lugs
17 = steel 35.5 mm case, bombe lugs
34 = 18k gold 36 mm case, straight lugs
55 = steel/gold-capped jet case
57 = steel/gold 33.5 mm case, bombe lugs
60 = steel 35.5 mm case, bombe lugs
69 = Sub Piquerez compressor case, 1st execution
63 = 35.5 mm gold capped case, bombe lugs
65 = upgraded 35.5 mm gold capped case, bombe lugs
66 = 35.5 mm steel compressor case, bombe lugs, thick bezel
68 = 33.5 mm steel non-compressor case, bombe lugs, thin bezel
Time-Date cases, e.g:
503 = smaller case, bombe lugs
504 = smaller gold-capped case, bombe lugs
601 = smaller case, bombe lugs
602 = steel Jet case
604 = gold-capped Jet case
605 = gold-capped case, bombe lugs
607 = smaller steel case, bombe lugs
610 = smaller steel case, bombe lugs
612 = larger steel compressor case, bombe lugs
The sub-reference numbers that follow (e.g. /01, /02, /03, etc) refer to the dial layout, and varies in meaning according to the reference number it is assigned to. We can see these in the Reference Gallery, and descriptions in the Reference Tables.

So, looking at the above example, we can see that the 20217-1 can be broken down into:
2 = steel case;
02 = automatic bumper movement, time only;
17 = steel 35.5 mm case, bombe lugs;
-1 = black dial, no lume (see Reference Tables and Reference Gallery).

And by deconstructing the reference number for the 104503-1, we see that:
1 = 18k gold case;
04 = automatic microtor, time and date;
503 = smaller case, bombe lugs;
-1 = gold dial, without lume (see Reference Tables and Reference Gallery).
So, what happened that changed all this?
Post-1965 polerouters
In 1965, Universal Geneve updated the “code” for their reference numbers, and hence the numbers changed for each model. The update from the calibers 218-9 (time-only) and 218-2 (time-date) to the new calibers 68 (time-only) and 69 (time-date) seems to have happened around the same time. An example that shows these changes is in the back of the 1965 UG Catalogue, listing “previous” (bisherige) model numbers, and their “new” (neue) equivalents.

From this, we can see that the 204612 and the 869106 is essentially the same watch, with an updated movement (from caliber 218-2 to caliber 69) and an updated reference number. The numbers representing the movement type changed from being a “code” (e.g. 02, 03, etc.), to the exact caliber number inside the watch (e.g. 68, 69 etc). Subsequently, the 204605 became the 869102, and the 204612 became the 869106.
This infers the “new” numbering system, which was in place from 1965.
First number – Case material:
1 = 18k gold (later changed to 2)
2 = (as above)
3 = 18k white gold
5 = gold-plated case
8 = steel
Second number set – Movement:
68 = caliber 68
69 = caliber 69 / 1-69
71 = caliber 71
72 = caliber 72
Third number set – Case style, e.g:
102 / 106 / 108 / 111 / 112 / 113 / 114 / 115 / 116 / 118 / 119 / 120 / 121 / 123
The sub-reference numbers remained a descriptor of the dial, again unique for each model reference number.
Polerouters were not the only models which used the coding system. It seems that UG used this system consistently throughout their entire model range for this period. The same coding system can be applied to other UG models and help collectors to identify incorrect watches, particularly the lesser known/studied ones, such as the Monodate / Monodatic range, or those which did not have a descriptive model name.
