Help Identifying IWC pocket watch

Hello everyone !

Help Identifying IWC silver pocket watch

Thank you

Looks like a nice Cal. 57 from the 1920s. The "Date Your IWC" app is not functioning for me, so I am unable to confirm. The beautiful "cathedral" hands have lost their luminescent material, which is why they look hollow. The dial looks like it may have also been originally lumed with radioactive material that was later removed. 

Thank you Ben !!!

Ben is correct - Cal 57 from 1925

Cased around 1926