An inhaler comprising a breath operated valve with a valve element biased closed by a spring and a diaphragm arranged to deform when suction is applied to an outlet end generating low pressure above the diaphragm to lift the valve element against the biasing force of the spring allowing composition to flow out of the inhaler. The spring is a strip of resilient material forming a U-shape with a first arm extending from a position adjacent to the valve element along the diaphragm in a direction away from the outlet end so as to support the diaphragm to an apex where it extends away from the diaphragm into a second arm extending back towards the outlet end, the second arm engaging with the housing to generate a biasing force to urge the valve element closed.
