Having gotten our new helmets up & running, I decided to tear down my old helmet to see what’s inside. The thin plastic shell was already cracked (and probably brittle from years of sun), so it tore off very easily. The foam structure was in good shape, but I was surprised to see that everything’s held in place by glass filament tape!
The straps pass through an H-shaped locking clip tucked into a recess in the rear apex (to the left in the picture). The front strap simply loops over the foam shell (to the right of the tape crossing on the right), where it’s held in place on double-sided adhesive foam tape by the glass filament tape.
All in all, a low-cost, low-weight design that works just fine.