STP caliber STP1-11 is a Swiss made automatic watch movement with 26 jewels. STP stands for Swiss Technology Production, however, you will mostly see this manufacturer simply referred to as STP. Their website also references the name SwissTP. Whatever you call it, STP is a Swiss factory owned by Fossil Group with a production rate of about 100,000 movements per year.
STP1-11 VS STP1-11M
There is also a similar caliber STP1-11M which is the non automatic version of the STP1-11. The manual wind version is slightly shorter at 3.7mm but has the same case fitting diameter of 25.6mm. The beat rate is the same, as well as the power reserve, but the jewel count drops from 26 to 20 without the need of an automatic wind unit.
The STP tech sheets claim an accuracy rating of -0/+15 seconds per day, operating within a max amplitude of 320 degrees and minimum amplitude of 200 degrees. Each movement is tested in 5 positions.
We couldn’t find an official version of the STP1-11 without a calendar complication, but found a watch brand that had STP modify the STP1-11 for a no-date watch. so it is possible:
“The movement is modified to a no-date movement, all components related to the date have been removed. Upon request STP has adjusted the movements that there are only 2 crown positions, one for winding and one to set the time.” –Méraud Bonaire