It is perfect to quickly and efficiently measure the height arch to decide on the best footbed to use. this can be used for bike fits, as I do, but also for any kind of footwear application.
This naviculometer is based on the Purely Custom, Trek and gebioMized versions (which i believe are identical, just a different brand printed on them). I am not sure of the size of these as I don't own any of them but after a few trial and error I found the sizes and the angle are the best.
The handle is ok but doesn't feel great so it will be redesigned in the neat future.
The author hasn't provided the model origin yet.