Here are a few pics of chin strap ends and buckles. All recovered from dugouts over the years using a garden sieve.
You can see there are many variations of the 1891/5 pattern attachments and buckles. Some are cleaned and some are as found. Some are really crude in manufacture and some are very delicate.
The pics leave a lot to be desired, but it is 3 in the morning and I have had a few glasses of vin rouge

I really need to get this photography thing sorted out.
As you can see the pics confirm the genuine nature of the "thicker" 1891 ends mentioned by Brian (if there was ever any doubt) One point of interest though is the fact that one of these early attachments is twice as thick as the other. I tried to photograph this but with a flash as my only light and no stand, they were blurred, glary and of no value. Were these issued for use with the stahlhelm, or were they just a manufacturing diff? They do not fit on an 1895 stud, but they will fit the slightly longer 1891. However, there is no way a cockarde is going on there aswell. Maybe they were private purchase? I have no idea..it is very very heavy manufacture.
As I said all of these are 100% original, but some of them are so off center and poorly made I would call them fake or remakes if I saw them on a strap on ebay for example.
The pics are rubbish I know. I also have a few complete and partial straps I have found over the years. I gave up trying to photograph them, but I will get them posted as soon as possible.
A couple of interesting points about the straps I will mention. All the straps I have found that were assembled with stiching as opposed to a rivot, were stitched using only 3 holes. Some of the pics on here and some of the straps in my own collection have 4 or 5 holes. Is this just wartime economy, for speed of manufacture or just pure chance and it depended entirely on the chap with the needle in his hand? Also not all the ends on the straps I have found actually match. Most do, but on one example for sure, and on another that im pretty certain matches, the ends and buckles are actually different. Not by a lot, but enough to notice.
I have actually used a few of the ends that matched to remake straps for my own collection. I use old suitcase straps or similar, and if its to heavy, I use my wood lathe with a blank wrapped in 60 grit to thin it down. In my opinion they look far more pleasing than the repro straps on the market and atleast I know the fittings are 100% genuine. I can almost hear the purists groaning in the distance :lol: They make a far better stand in than all the repro straps I have seen, and when I replace them with an original, they move to the next helmet missing its strap. I will post a few pics of my remade straps at some point.
1915 buckles at the top. See the diff. in thickness on the centre bars on most of the 1891/5 buckles. 3 in the middle are all very similar, the bottom row are all different, I think bottom right may well be private purchase? The 1915 pattern buckles at the top are all different, in size and shape
Look how out of line the `V` notch on the top left one is, also the heavy early pattern 1891 mentioned by Brian in the top row, look how badly made it is. The one below it has a much wider slot for the leather strap. The second early pattern end on the bottom row is twice as thick as all the others. This is just a selection of the ends I have found over the years, but it serves to show the variety of manufacture in chinstrap metalwork.
Just another slightly better pic of the 91/95 ends.