Hi, the plastic strip is real swine to fit, I ended up trying to warm it and lie it flat to remove the kinks from being sent it folded up. I managed to clip the loose hanging part when trying to slide it onto the gutter rail. I too got very frustrated but managed it in the end. Once fitted it has to remain in place whilst travelling, I consider it very unlikely to come off as it's so hard to get on in the first place.