Ahh. Yep those glass refractors are still made nice and sturdy. It's only a matter of time before the prismatic glass refractors start getting thinner and thinner.
I have noticed the refractors getting thinner over the years especially the AE 125's. FCO 125's are starting to get very common now. Looks solid but easy to break if it fell.
The FCO glass is very thin becuase it's only a clear sheet of glass. About as thin as the glass shelves in your fridge and it's the same type of glass. Prismatic refractors like above are thicker since they have prisms and such. Plastic refractors are pretty much all paper thin nowadays except for the Formed Plastics lenses. Glass lenses seem to still be pretty thick. The glass that the GE M-400s used was pretty thin, even in the 70s and probably since the M-400 first rolled out. The Westinghouse glassware was pretty thick though and the small sized GE fixtures had really thick glasses too.
Thinner refractors are better lumen wise since more light can pass through a thinner refractor but thicker refractors are more durable.
Thinner refractors are better lumen wise since more light can pass through a thinner refractor but thicker refractors are more durable.