Vecamco FLUSH FITTING RECTANGULAR PLASTIC AIR VENT WITH INSECT/MOSQUITO NET 270mm x 120mm x 16mm Suitable for internal an external use. (black)

does what it says on the tin

I was looking for an flat air vent to attach to a my covered chimney with air holes.Based on the Image, description and sizes mentioned, I thought this was a flat air vent.The air vent actual has a moulded box attached to the back of the vent. This is not mentioned.If it was mentioned, it is not obvious in the description.So for me this is Totally the wrong item. The seller should of supplied a picture of the reverse side.No point in returning it, the recorded delivery will be more than the item.