Metric wing nuts have protruding 'wings' to make hand tightening and loosening easier. Wing nuts are used when a part is often assembled and disassembled by hand, where no more than finger pressure is needed. They may be used with or without a washer.

The ease of use also make wing nuts popular for applications in which convenience is vital, such as on boats and bicycles.  Stamped wing nuts feature hollow wings open at the top. Cold-forged wing nuts are solid parts.