Differences btw 2 belt hooks

[Christophorus]

Hi,
I own these two kriegsmarine belts hooks.
Could you explain me their use and why they are different please???
All the best
Cédric

[phild]

The one on the left is designed to be removable and for a jacket with holes and straps to accommodate this type of back button hook. The one on the right is sewn in.

[Christophorus]

Thank you phild for your invaluable help.
I assume they weren't worn during the same period of the conflict.
For you, which one was worn at the begining?
For officers? Petty officers??

[phild]

Thank you phild for your invaluable help.
I assume they weren't worn during the same period of the conflict.
For you, which one was worn at the begining?
For officers? Petty officers??

You are more than welcome.
I do not know exactly what year that the basic design of this button was adopted. I assume mid 1930s. I mention this because I’m trying to establish what pattern tunics these were made for. I believe they would have been for very early patten 1920s (1928??) Navy land pattern tunics in feldgrau. If so, the left one was for a summer tunic and the right one is for the wool version.

Both of these basic designs (not the Anchor motif) date back to WWI period. In my experience the one on the left is very seldom seen.