I have somewhere around 150 feet of Zehnder 3" Comfotube leftovers, mostly in ~8 foot lengths. I'd prefer to see them put to use rather than put in a landfill.  If someone wanted to save a few hundred on a Zehnder install, or had another good use for them, I would give them to you.  I'm located in central VT/NH, near the intersection of I-89 and I-91.  I hope such an offer is acceptable to post here.