It sold like hotcakes so it really did not need any advertising. The Convertible line of cleaners sold so well that the Hoover advertising of the time seems a bit "soft". I think that they pushed their other appliances much harder. They really wanted to break out in the late 1960's product for product with other manufacturers to have a more complete line of appliances. It was a short lived venture in the end, but they made some fantastic cleaners during this time.
--Tom