This is a cover from Sautes, Grenada in 1977. It was sent to Radio, Antilles on 6/29/1977. The postage due was paid by a 10 Cent Grenada stamp, as well the Montserrat Flower Issue 3 Cent and 10 Cent stamps! This is a real RARITY!
Take care because this item, though in very good shape, is still extremely old!