Granny's historical bathing costume dates back to the early 20th century.
The final short where Bea Benaderet voiced Granny. Starting with Grand mère ne s'en laisse pas conter (1955), she would be voiced by June Foray.
Granny mentions her bikini bathing suit. Although the bikini hadn't yet become hugely popular in the US, it dates back as early as July 5, 1946 in postwar Europe. The bikini would have its heyday in the California surf craze of the 1960's, though it continues to be celebrity swimwear of choice in the 21st century.
Tweety is shown wearing the latest (for the era) style of fashionable sunglasses.
The curious inflatable item Sylvester blows up was known as a water wing flotation device. It was a popular novelty for nonswimmers at the time.