Don’t leave your condoms in the sun too long. Makes for a surprise after beach blanket bingo.
The UV makes sense. I bought my binoculars for a trip to Patagonia, Tierra del Fuego and Cape Horn, about the time of the notorious “ozone hole” down there which let in excess UV to Earth’s surface. It happened almost immediately. I thought maybe it was a chemical in the sunscreen on our hands, but it was good ole UV apparently.