This is a German WWII RLB Reichsluftschutz gladiator helmet (Air Raid Protection helmet).
Kopfweite 55, which is a nice size.
In very good condition with most of it’s dark blue color present and only minor age damage (dents). The decal on the front is in good condition too. The whole helmets has a “shiny” appearance” which is caused becaused it was oiled at the time (it’s not sticky and feels just like regular paint on all RLB helmets).
Complete with liner and chin strap.