Crown fastener and method for using

摘要

An anti-loosening fastener comprises a head having an upper side and an underside. A shank extends from the middle of the underside of the head. A nut, a concentric counter-bored section and a gripping surface are formed in the upper side of the head. A plurality of protrusions are disposed radially along a perimeter of the underside of the head. A method of use is also provided.