So far, when I visited a Dan Flavin fluorescent light fixture sculpture exhibit at the Norton Simon Museum in Pasadena, California, I have seen what appear to be specially reproduced fluorescent tubes that are no longer manufactured or banned in the USA that have no etches whatsoever. For example, I have seen what appears to be a genuine F40WW fluorescent tube and also some colored fluorescent tubes with no etches whatsoever. I think that the tubes were specifically manufactured in order to maintain Dan Flavin’s fluorescent light fixture sculptures and preserve their original beauty as I am pretty sure that the artist wanted to maintain the beauty of halophosphate fluorescent tubes.