From The Anvil Aged Bronze Traditional Letterbox

Description

For composite and upvc doors we would recommend using our door letterbox which is supplied as a full kit and contains a tunnel and brushes to reduce drafts and insulate the door. The sleeve inside the letterbox also protects the door from moisture and masks the aperture cutting.
This finish is manufactured from solid bronze containing a minimum of 85% copper. The finish has a rich, matt look and is very dark due to the process used to age the metal.  To preserve the dark tones of this finish, we apply a durable matt lacquer at the final stages of manufacturing.