duct tape is the way to go. I use aluminum HVAC tape now.my aero brand ones had the same size inner and outter flare.. pita to put it in the box that way //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif gotta glue it on from the inside.. maybe duct tape would've been a better option but I glued it LOL