I have several digital thermometers and when someone starts complaining about feeling hot or sick I want to see if they are running a fever. Usually I wipe the end of the thermometer off with an alcohol wipe but wanted something that I could use without having to wait for the alcohol to evaporate. I had seen the prove covers at the pharmacy a couple of times and decided to get a box so I could line up the boys and take their temperatures one after another. They didn't like the feel of the covers on the thermometers or in their mouth under the tongues; I thought that they might just need to get used to the feel of the cover under their tongue but that wasn't the case. The prove covers do fit almost all flat digital thermometers and can help to reduce the spread of germs but if kids don't like the feel of them then they are going to be a wasted purchase. You get fifty of the covers in a package and they are individually sealed; to use them just open the one end of the packet and slide the thermometer into it. When you are done with it, dispose of the cover in the trash. Do not flush them because they will end up clogging your pipes. I have never tried these with regular standard thermometers and I don't know if you will get an accurate temperature reading from them if you use the covers on them. Even though my kids hated these when they were younger i think they are a great idea for anyone that has kids or runs a home daycare. They can cut down on the chance of germ transfer and eliminate the need to sanitize the thermometer after each use or between uses.