What sucks is when bits of your bumper are ripped off with the liner when it makes contact with the wheel
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The liner and the clips all kind of work together to hold shape. You can lose a few clips, here and there, but they're all basically needed and cheap. I only have the clips break after they've been reused, so I treat them like disposables. Most people use a flathead to pry them open, but I've found this damages them. There's a special tool for popping them out, but at 6$ for a bag of 50 for the clips, it seems not worth it