WW2 German Kriegsmarine Coastal Artillery badge by the much appreciated, amongst collectors, manufacturer Schwerin Berlin. Nava badges from Schwerin are reknowned for their high level of detailing, the way that they maintain their gilding / wash after many years and their robust hinge and pin set up (you dont find many with a broken / repaired reverse).
Note -> As always the problem with being a much appreciated antique badge is that they are also the first to be copied and reproduced. From the images shown below there is more than enough detail to make a comparison for authentication purposes.

Close up of Eagle showing little gilding remaining

Cannon body showing detail of steps and handrail. The Schwerin CArt badge is distiguishable by the level of detail employed.

Clear crisp detailing of the breech mechanism. Many identifiable features which on copies / reproductions of the Coastal Artillery badge tend to be forgotten or poorly copied.

Reverse of WW2 german Kriegsmarine Coastal Artillery badge

Hinge mechanism which if badge were unmarked would alost be a good enough indication for attribution to Schwerin on its own. Pay particular attention to the tooling marks which are only reallistically visibile with a magnifying glass.

Flatwire catch sitting upon a mounting disk

Manufacturer marking “Schwerin Berlin” in block capitals and relief on the reverse of the badge.