I am replacing an white plastic internal vent on the kitchen wall(leads to an airbrick). The size of the vent is 10.5 x 7.5 inches. All the vents I have seen at B&Q are 9 x 6 or 9 x 9 inches.
Looks like I will have to fill in the "hole in the wall" slightly and insert new screws.
Any other ideas ? I will be putting wallpaper up around the vent.
Bruce