This is an original German M18 helmet. The shell is size 66, and was made by C. Thiel & Soehne, Luebeck. This model came out in the summer of 1918. It was an upgrade on the M17 with a new more efficient chinstrap system. These helmets were worn well after WWI. This is the helmet of the Reichswehr, as well as the Allgemeine SS. In the late 1930s many of these shells were re-worked for the Heer and Luftwaffe as well. The buyer of this helmet has a lot of options for restoration. For the sales price you get the shell painted to your specs, with a liner and chinstrap. The following options are available:
Liner: M18, M20, M24, M31 aluminum unreinforced, M31 reneforced, or M31 steel
Chinstrap: M18, M27, or M35
Decals, camoflage patterns, and aging are all available on request.