I had the plastic side of my HE350's break in my backpack and wanted to get them fixed. I talked to the manufacture and they were really great, but since I bought them used by a 3rd party, it would still cost me a little as the warranty was no longer in effect. To save money I tried the self fix. So I tried the basics - Super glue - Worthless, Locite for plastic - Worthless. Finally I tried the winner, JB Weld epoxy . Because of the small amount of surface at the break I covered a large area to make sure it was done. Here are the before and after; as I said it is not pretty, but this will never break again here . Before After The fix is in the backside or I would clean it up more.