This is a 1981 Massachusetts FALL INSPECTION Sticker. They were issued from October, 1981 to April 1982.
Notice the big R on this sticker indicating that it was a replacement for a previous sticker that fell off the car because of inferior glue by the manufacturer.
These are "peel and stick" stickers BETTER than the originals and they attach to the inside passenger side of the windshield.
The backs allowed for personal car information.