a question
hi Mike,
I have a question:
I bought some 2nd hand equipment from a scientific-lamp-worker,
who bought lots of stuff from a retiering glass-blower.
One of the items I bought was a protective clip-on.
it has a pale light-blue tint, which turns to purple-pink when
seen under flourecent light.
he couldn't tell me the origin of it, because he didn't ask the old man.
i use it, it filters the sodium flare alright, my eyes feel OK, but I don't work too often.
I have no idea what I have in hand.
it doesn't LOOK old, but one can't tell.
can you help me identify it?
thanks.
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