Each blank challenge coin will be paired with a plastic protective box, aims to provide better collection effect and protect it from loss or scratch. These blank challenge coins are made of high-quality solid brass with non-electroplated brushed finish, durable and rust resistant, not easy to fade, break or deform, easy to carve. This set of blank coins is ideal for laser engraving, can be engraved into a variety of patterns or words to friends, family, friends as meaningful gifts.