Flamebreak Solid Core Door Blank 7'x3' is a 44mm thick external door blank with 4mm hardwood ply face and FD30 fire rating tested in accordance with BS 476-22 and BS EN 1634 -1' is a 44mm thick external door blank with 4mm hardwood ply face and FD30 fire rating tested in accordance with BS 476-22 and BS EN 1634 -1