This is a rare Infanterie Sturmabzeichen (ISA) / Indantry Assault badge.
It is an unmarked badge but can with certainty be attributed to maker S&L (Steinhauer & Lück from Ludenscheid).
This particular variation is very hard to find.
In excellent condition with 100% silver finish.
(Because of it’s shiny surface hard to photograph, i used photoshop on it, the surface is like a mirror, really nice!)