They aren't as hot as you may expect; you merely sweat in them and it sticks with you. When you remove the mask at the end of the night, it produces this really distinct noise. It's kind of addictive to listen to it. Silicone is a material that doesn't react with anything so it can be used for making medical products, food packaging, and clothing items. The most famous product that is made from silicone is the condom because it can stand up to heat and moisture. People often think that condoms made of plastic are more durable than those made of rubber but they can break down over time if you throw them away often enough. Condoms that are made from silicone will last forever. The next time you go out for laser tag play or other activities where you need to wear a face mask, know that it isn't going to burn your face off like you might expect from something made of rubber. Silicone is a material that can actually help reduce the temperature of your face during these types of activities.