I used the AC ducting for running my roof mounted Traveler dish control cable. Works really easy IF the duct is accessible close to the destinations. On mine the duct was within a foot of my AV cabinet and I removed a ceiling light in that area so I could get my hand into the ceiling and route the wire from the duct into the AV cabinet. On the other end it was about 2 feet from the hole in the roof but I could see the duct and it was an easy routing into the duct from there. I could have easily ran a HDMI cable to my TV the same way but I already had a factory one
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