An exhaust treatment component may be mounted in brackets, each bracket having a clamping surface which in a use orientation is arranged in parallel with a corresponding mounting surface of a fixed mount, the mounting surfaces defining adjustment planes which are spaced apart along a length axis of the mount. Each bracket may be adjusted independently in its use orientation to define a variable clamping position in the adjustment plane. In another aspect, the component may be mounted in one or more brackets, each bracket comprising curved contact surface, each surface being defined by an arc of a respective circle, each arc being contained in the circle of the other respective arc, whereby the centre points of the respective circles are spaced apart in the reference plane so that each arc is contained in the circle of the other respective arc. The component can be clamped to the bracket irrespective of its diameter.