The stamped sheet steel construction helmet retains most of its slightly rough textured, Luftwaffe blue/gray paint. The left side of the helmet has a second pattern (circa 1936/1937-1945), Luftwaffe eagle decal which is retained about 85%. All three of the liner retaining rivets are intact. The interior of the helmet has its original M31 light tan leather liner fully intact including the tie string. The reverse interior neck guard apron has a number stamp "12230", and the interior left side apron is stamped with the manufacturers code and size "hkp 64" indicating manufacture by Sächsische Emaillier-und Stanzwerke, AG Lauter, size 64. Also comes with an original chinstrap. The first "modern" steel helmets were introduced by the French army in early 1915 and were shortly followed by the British army later that year. With plans on the drawing board, experimental helmets in the field, ("Gaede" helmet), and some captured French and British helmets the German army began tests for their own steel helmet at the Kummersdorf Proving Grounds in November, and in the field in December 1915. An acceptable pattern was developed and approved and production began at Eisen-und Hüttenwerke, AG Thale/Harz, in the spring of 1916. These first modern M16 helmets evolved into the M18 helmets by the end of WWI. The M16 and M18 helmets remained in usage through-out the Weimar Reichswehr era and on into the early years of the Third Reich until the development of the smaller, lighter M35 style helmet in June 1935. In an effort to reduced construction time and labor costs minor modifications were introduced in March 1940 resulting in the M40 helmet. Further construction modifications were undertaken in August 1942 resulting in the M42 helmet.