Lennox - 12M20 with H6823 door track kit 38LBF - 38" Solid Ribbed Extruded Doors - Black - Used for Superior fireplace models: LBC3824 LBC-3824 LBC3824-H LBC-3824-H LBR3824 LBR3824-H LBR-3824 LBR-3824-H - Part # / Catalog #: 042803, 066973 042801 and 066971 - Manufactured before August 2000