They seem durable enough to do the purpose. I live in an old 1900 house that outlets were added on later in years(those were considered standard size at the time),Most are the three prongs outlets. These covers just barely cover the third ground within the outlet. If I had the simple newer home that only have the two prongs outlet,these will fit perfectly.
I mainly got these because after experiencing a slight shock when plugging in a blowdryer,Due to dust built up in the inside of the outlets. These makes life less surprising shocking experience...lol!