Device for controlling fluid flow

A device for controlling the flow of a fluid through a conduit from an upstream side of the device to a downstream side of the device, the device comprising:

• one or more valve apertures through which the flow of fluid is selectively controlled;
• a valve member arranged to move reciprocally to selectively open and close the one or more valve apertures, thereby controlling flow of the fluid through the one or more valve apertures;
• a stop for arresting the travel of the valve member arranged at or beyond a position the valve member reaches when at least some valve apertures of the one or more valve apertures are open;
• and
• wherein the valve member comprises an end portion arranged to come into contact with the stop when the valve member reaches or passes the position at which at least some of the one or more valve apertures are open, and comprises a body portion, the end portion projects from the body portion in a direction towards the stop, the end portion and the body portion each have a maximum dimension in a direction substantially perpendicular to the direction in which the end portion projects from the body portion, and the maximum dimension of the end portion is less than the maximum dimension of the body portion.