Storage lockers are a type of UNIT used for storing items. They are typically made of metal and have a door that can be locked with a key or combination lock. They are often used in schools, offices, and other public places to store personal items such as coats, backpacks, and books. Storage lockers can also be used in homes for additional storage space. The term 'storage locker' is typically used to refer to the four-letter UNIT.