Fully tested original Apple logic board for a Macintosh SE FDHD. This was originally fitted with a 1.4MB (FDHD/Superdrive) floppy disk drive. For an SE that was originally fitted with an 800K floppy drive which was subsequently upgraded to a 1.4MB floppy drive, you should use logic board part number 661-0526.
Logic boards from machines that were originally fitted with 1.4MB floppy disk drives can be easily identified by the fact that their backup battery is removable and in a plastic holder. The battery on versions originally fitted with 800K floppy drives are soldered onto the logic board.