British Homefront Medical Rescue Helmet, 1939.
Here's a variant that ive never seen before being a 1939 dated Rescue Helmet with Medical Red Cross painted to the front and back. The black finish is around 80% complete , this black has been painted over what was once an early Army helmet with the early pattern liner. The liner is dated 1938 and the helmet being 39 dated. I would rate the condition as very good.