Abstract: A quick release for a bicycle has at least one eccentric cam provided with a bearing bore by which the cam is rotatably mounted on a shaft, which is fitted to a component, which can be secured with the aid of the eccentric cam to a bicycle. The eccentric cam can be rotated by a hand lever into a clamping position and can be released from the latter by rotation in the opposite direction. The hand lever is constructed as a lever arm which is substantially U-shaped. The two free ends of the legs of the U-shaped lever arm are, in each case, arranged in a lever arm fixing bore in the eccentric cam and have a channel, which engages around the shaft, through which the level arm is fixed in the eccentric cam.

Abstract: The invention relates to a single-shell helmet made from a styrene or polystyrene-based foam plastic. Unlike in the case of the hitherto known one-piece helmets of this type, the invention subdivides the helmet into shell parts, which are integrated together by means of hinged areas and can be easily adapted to different head sizes by means of an adjusting system.