Silicone deformed? Silicone very springy and tough unlike rubber. Probably something fake....My PIAA ones came with multiple different clips to clip onto the wiper arms. Also Duraplus silicon wipers are absolute crap. The last time I used this wiper the silicon (supposed to be silicon) deformed and the metal bracket holding the wiper had direct contact on my windscreen. So it basically scratched the windscreen like hell and there wasn't anything I could do since it was raining.