What are speed clips that hold rotor?

Speed clips, in the context of rotors (typically brake rotors), are small, spring steel clips that are used to secure the rotor to the wheel hub. They're also sometimes called rotor retaining clips or hat clips. They work by fitting into specifically designed slots or holes in the rotor hat (the central part of the rotor that attaches to the wheel hub) and the hub itself. The springiness of the clip keeps the rotor firmly in place. They are a common alternative to screws or bolts for fastening rotors, especially on many car models.