From what I've heard and been told it's the brackets that the tour packs mount to that seems to be the main culprit, the latch slots the bushing are supposed to slide into are all over the place as far as sizes go, which is why some people's seem to fit perfect and others break the first time you slid them on (or I should say try and slid them on ) I made some and have a few out there but decided not to sell them till Harley got there end squared away (the FMJ's have no give in them ) the sissy bar mount seems to work ok though