I'm finishing the basement putting in a batroom, bedroom and a large familyroom. I have put in two lines off the heater but would like to tie into a 6 inch duct for the bedroom and also the other end of the family room. They have a section that snugs up to the 6 inch duct that is like a half of duct with it's own 6 inch duct off of it but it hasn't been crimped and neither is the next section od straight 6 inch duct that has a rectangle end for the vent opening. Also even if one end was crimped it would hang to low for the drywall cieling I will be putting up. Any ideas would be greatful.