German Luftwaffe (Air force) qualification badge for Radio operator & Air gunner roles. The lightening bolts in the Eagles claws signify the Radio aspect. This example was produced by W. Deumer of Ludenscheid.
Please note that all Luftwaffe badges by this manufacturer (and indeed other manufacturers) are heavily copied due to their economic values within the medal and badge collecting community.
2nd World War Nazi Germany Luftwaffe Flak kampf abzeichen with the unusual marking of L/11 whilst the badge features and reverse hardward set up (see hinge and catch photos) are consistent with those of a different maker / manufacturer.