Rear window defrost for a "66 Baracuda?

My father showed me something on his '66 Baracuda that looks like a space for a rear window defrost on the passenger sidemoldings right above the wheel well. Was there a model that came with a derost or is this some kind of vent? It's a factory cut piece on both pieces, but we're njust not sure what it is.

The 64, 65 and 66 Barracudas have an ingenious air flow system built into the sub chassis, air is collected through the chassis and blown through elongated slots in the rear trim to keep the glass clear. Glad they did as a demister would have looked awful on that rear window.

Zeus

There was an option for a rear defroster motor and fan that mounted into a hole that looks like it is for a 6 x 9 speaker on the right rear side and flexible tubing ran to a duct that fastens to the slot you are referring to. I bought a wrecked 65 back in the early 70s that had that option and a factory reverb unit for the radio. I took the body pieces I needed and sent the rest to the salvage yard. Sure wish I had both of those items now.....

Those slots actually defrosted by flow through ventilation too,as previously mentioned. Check out the rubber flaps at the top front of the trunk opening. That's where the air goes out from the slots around the back window.

Got it. Thanks guys.

I saw a great you tube video once that showed a cross section of the chassis and how it works, damned if I can find it again.

Zeus