A hot air gun having a hot air outlet is provided with a guard plate having a substantially straight edge transverse to the general direction of the hot air flow. This straight edge is downstream of the hot air outlet and defines the downstream extremity of the guard plate, the latter defining the boundary on one side of the hot air flow from the outlet. Preferably the guard plate has a flared flat part and a tubular part, the latter being detachably and rotatably mounted around the outlet. The guard plate is advantageously used when stripping paint adjacent a glass pane to minimize heating of the glass.