THIS IS AN INTERESTING CANADIAN VARIETY STAMP. THERE APPEARS TO BE AN EXTRA PULLEY ON THE SIDE OF THE BOAT. THIS OCCURRED ON SCOTT 747 THE 12 CENT MACKINAW BOAT PART OF THE SAILING VESSELS ISSUE. IT WAS ISSUED ON NOVEMBER 18, 1977. IT IS IN VERY NICE CONDITION. IT IS A USED STAMP. FOR OTHER ITEMS OF PHILATELIC INTEREST ESPECIALLY ERROR STAMPS, ANTIQUES AND VINTAGE COLLECTABLES PLEASE VISIT MY OTHER ADS.