This is an Infanterie Sturmabzeichen (ISA) / Infantry Assault Badge (IAB) maker Steinhauer & Luck.
The badge is not visibly marked, but can with certainty be attributed to maker Steinhauer & Luck from Ludenscheid.
In very very good condition! Most of the silver finish is still present, very hard to find like this!!! It would be hard to find a better one!