Heat protectant products are liquids or sprays that you apply to your hair before doing any kind of heat styling. These magical potions protect the hair and mitigate the damage that high temperatures cause to the hair. This is important because high heat (anything over 266 degrees Fahrenheit) will damage the cuticle, leaving the hair coarse and dry, damage keratin proteins, making the hair weaker, and damage the hair’s pigment, making it turn brassy.