Abstract: A disc brake operating piston includes a hollow, cylindrical body which is open at one end thereof and is closed at its opposite end by an integral base member. The body is formed of a synthetic resin material and the base member is provided with an upstanding projection which is fixed relative to the base member and which extends to a position for engagement, in use, with the backing member of a disc brake friction pad. At least part of the projection is defined, over the whole length thereof, within an area bounded by a circle concentric with the body and having a radius up to one half of the radius of the bore in the body at the base member.

Abstract: A fluid pressure transducer includes a hollow body divided into first and second compartments which are sealed from one another, the first compartment being connected, in use, to a first source of fluid at a pressure to be monitored, while the second compartment is connected to a reference source. The compartments include a common wall which is deformable in response to variations in the pressure of the first fluid source as compared to that of the reference source, and received within the body are a carrier and a first abutment member which are capable of relative movement towards and away from one another in resonse to deformation of the common wall. A plurality of further abutment members are resiliently supported by the carrier and arranged so as to become engaged with or disengaged from respective portions of the first abutment member at different positions of the first abutment member relative to the carrier.