Jenzi & Pfaff from Pforzheim in Germany producted until the 1960ies in rather low quantities wristwatches, branded as "Hercules" and movements. The second caliber family after WW II contained the calibers 102, 103, 125 and 126 and was already 1957 superseded. The HPP 125 has got an indirectly driven center second and a shock protection.
With a diameter of 13 lignes, the HPP 125 was virtually hige, and in conjunctin with ruby bearings (everywhere, except for the minute wheel) and a large screw balance, it was capable of delivering good precision rates.
The gear train is a true classical one, with fourth wheel at "6", third wheel, acting as transmission wheel for the indirect center second, and directly driven minute wheel.
Of course, this movement works with the usual slow 18000 A/h. It uses a swiss type pallet lever.
The large screw balance with its waisted legs is beared in two inhouse "Shockproof" bearings, which only protect against axial hits. It does not protect agains lateral shows, since only the cap jewels are resiliently mounted.
An interesting detail are the extremely massive screws. No other movement uses such strong screw heads. A true "Hercules" thing.
On the dial side, the case caliber numer, 102, is used. Interestingly, HPP marks it as "HP" here.
Besides the cap jewel spring for the balance shock protection, you can see the yoke winding system and the lateral screws for securing the dial. This advanced construction perfectly secures the dial without putting bending force onto it.
At "6 o clock", you see the fourth wheel bearing, if it was the caliber 102, the axle would be longer to carry the decentral second hand.
In the lab
The specimen shown here came resinified into the lab and got a full service.
Afterwards, it performed very well again in horizontal positions with an amplitude of 268°. In the vertical positions, it decreased to 150°, a sign, that the balance axle more or less reached its end of life. Additionally, the dirt and magentizm of the hairspring could not be fully removed, so that from time to time, the movement speeded up to 3 minutes per day, which went away after a short time again.
Nevertheless, for 65 year old and heavily used (according to the case) movement, a very fair result.
This movement and watch is a donation from Erwin. Thank you very much!