THIS IS A PHOTOFACT(Repair info) FOR AIRLINE MODELS 74GSG-8810A & 74GSG-8820A AMPLIFIER.  IT CONTAINS SCHEMATIC(S), INTERNAL VIEW(S), PARTS LIST AND DESCRIPTIONS. IT IS A ORIGINAL AND NOT A COPY. THIS IS WHAT YOU WILL NEED IF YOU EVER NEED TO MAKE REPAIRS.  IT IS IN VERY GOOD CONDITION.BUYER PAYS S.H.