A hand held appliance comprising a fluid flow path extending from a fluid inlet into the appliance to a fluid outlet from the appliance, the fluid flow path being at least partially defined by a wall, a switch mechanism housed by the wall having a cooperating externally accessible actuating button and a switch cover extending within the wall and containing the switch mechanism. The switch cover may maintain a spatial location of the switch mechanism relative to the actuating button. The switch cover may encase the switch mechanism. The switch cover may isolate the switch mechanism from the fluid flow path. The switch cover may maintain a spatial location of the switch mechanism relative to the wall. The switch cover may be curved towards an upstream end to reduce disturbance to the flow of fluid within the fluid flow path.