A screw back is a type of earring back consisting of a threaded post and nut that secures the post inserted through the ear piercing to the back of the ear lobe. It is the most secure type of earring back because it cannot be pulled off. To remove the earring, the screw back has to be completely unscrewed and removed from the post. They are good for children and toddlers and for earrings with expensive gemstones because they minimize the chances of the earring falling off the ear.
