Running Vintage Zenith Tilden Thurber High Grade Oval Tank Watch Movement Manual

This movement is running but has not been tested for timekeeping and is being sold for parts, repair or restoration.

Possibly 1920s.

Tilden Thurber retailed watches for high end brands such as Patek Philippe 

I am not sure what calibre this is.

The balance wheel is intact, moving freely and ticking.

The hands are setting correctly.

The movement is winding correctly.