Here are some pics of one of my mint condition Schlueter M1 helmets. It came from a small batch of these I discovered in a scrapyard in the US around 12 years ago. I kept 3 and sold the rest. These pics are a few years old and I don't have them in a bigger resolution, although I do plan on making some new ones.
Description: Schlueter made, front seam, flex-bales (3 welding points), khaki chinstraps, flat metal buckle, paint mixed with cork. This dates it somewhere mid-late 1943 I believe. All the helmets in this batch were still in their original cardboard wrapper (not in the pics), and all in absolutely mint condition, except for some very minor scratches in the paint due to their 60-year storage, stacked on each other. A very rare find, and 100% original WWII. Enjoy!