I have a few questions regarding the evolution of Cairns Leather Helmets. Maybe you can help. Thanks.
"C" = Cairns
1. When did C switch from sized helmets to S,M, and L?
2. When did C add the suspension webbing (4 point or 6)? Was this when they also started adding chin straps?
3. When did C switch from hand written labels to typed labels?
4. When did C add the impact cap to New Yorkers (5A to N5A)and at what point did they switch from (I assume) fiberglass fillled (yellow looking) to grey plastic cap?
5. When did C introduce the N6A? How long was this after NFPA and OSHA started to test fire helmets.
6. When did C stop making size small helmets?

Obviously I am not looking for exact dates, but maybe year groups or transition times.