The office building my friend manages recently had cable TV installed from the street and into each phone room. I'm not really familiar with their outside plant stuff, so I was confused when I saw this cable running through the building. There is no plastic jacket, it's just aluminum (I think).
Perhaps Hal or someone who knows more about the CATV industry will chime in.

First floor, from entrance in the basement through the garage and up-
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Second floor closet
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This floor closet (end)
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Jeff Moss

Moss Communications
Computer Repair-Networking-Cabling