OEM Carrier Bryant Payne Furnace Control Board. P/N HK42FZ005 320639-101 Rev. It was sitting in the furnace room cabinet when we moved in (it’s not for the furnace presently installed) – while I cannot see the entire board due to the plastic housing, there is no evidence of burn marks or any unusual wear. Two of the three screw mounting holes do have some light wear, so it does appear this control board was installed at some point. Professionally packed in anti-static bag and sturdy box to insure your United Technologies Furnace Control Board arrives in the same condition as described in this listing.