The invention relates to a rotary lawnmower 100 comprising a cutting deck housing 110 which defines a cutting chamber 111. The housing has an aperture 112 to the rear through which grass cuttings are ejected from the cutting chamber in use. A deflector guard 120 is mounted about a hinge 121 at the rear of the housing, outboard of the aperture, for selectively deflecting the ejected grass cuttings. The deflector guard 120 is movable under a resilient biasing force provided by a helical torsion spring 122 from an open position in which the ejected cuttings are undeflected on their path from the aperture, through a deflecting position (A) in which the ejected cuttings are deflected downwards to the ground, to a closed position (B) in which the aperture is substantially closed. The lawnmower further comprises a movable stop 200 made from a resiliently deformable material. In a first position , movable stop 200 holds the deflector guard 120 in the deflecting position against the resilient biasing force of the spring 122, the spring extension arm 123 resting against the stop surface. In a second position, movable stop 200 allows the deflector guard to move under the biasing force from the deflecting position (A) to the closed position (B). The deflector will remain in the closed position in the absence of any external forces. In the reverse direction, movable stop 200 always allows movement from the closed position to the deflecting position.
