The 12-inch Telescopic Post Port Letterplate with adjustable telescopic sleeves fits doors 40 to 80mm. The letterplate includes an insulating brush strip that reduces cold & draughts and the flap opens to 180 for easy posting. Its fitted with sound dampening bumpers to prevent slamming. Fitting Instructions 1) Cut door aperture 285mm X 50mm 2) Separate the two letterplate halves and place the exterior gasket over metal fixing posts. 3) Take the half that contains brushes and insert into the aperture from the inside of the door. 4) Take the exterior half (with gasket) and slide into the letterplate tube from the outside of the door. 5) Before fixing. Take time to ensure the letterplate fully covers the aperture on both sides and that the exterior gasket does not protrude.
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