Does Anyone Know What These Are [on poles around downtown]?

[Jimaz]

It's a wrapping sorta -- I've seen them. Like tube that fits over the wire.

If you're referring to that orange line, that's just an arrow that was added to the original photo. It's pointing to the antenna. I made the same mistake the first time I looked at it.

I've also see red balls affix to the wires near Henry Ford Hospital.

There are a lot of those out west in mountain passes. They're to make the wires more visible to aircraft.