According to data sheet from manufacturer: http://www.tosoku-inc.co.jp/en/product/pdf/code/dp.pdf,
this rotary switch is DPP01 010 S16R
With the small screws the starting and end positions can be adjusted.
DP-series
with waterproof adapter (the aluminum disc with double sided tape)
Code Type: Real Binary Code
Step angle: 27.69 degree
Length of shaft: 16mm
What’s the difference between DPP and DPN?
DPP has the waterproof adapter (the aluminum disc with double sided tape)
Thus this item can be used as TOSOKU DPN01 010 S16R as well.
