Grommets are small rings or eyelets that are used for reinforcing holes in fabric or leather. They are also known as eyelets, washers, rivets, or metal rings. Eyelets are similar to grommets but are typically used in clothing and other fabric items. Rivets are a type of metal fastener that are used to attach metal pieces together. Washers are often used to prevent the grommet or rivet from pulling through the material. Metal rings can also be used in place of grommets or eyelets for reinforcement of holes. Whatever you call them, these small reinforcement devices play an important role in many industries, including fashion, automotive, and industrial design.