v1 is just the repaired and resized ldraw model of a similar helmet
v2 was my attempt to add some of the features to a preexisting ldraw helmet
v3 is a ground up redesign and the closest I got, I think
There is no saying what the back of the helmet looks like, your guess is as good as mine.
That is why I included all the major versions, you can choose which one you like best.
You can find the rest of my models for the non production Seatron parts here:
https://www.printables.com/@cbrick/collections/2187235
Also check out my monorail designs, including motors, stanchion, switches and track:
The author marked this model as their own original creation.