Flange Nuts or Hexagonal Flange Nuts have an integrated washer on the base of the nut. This helps even out the fastening pressure across the surface of the receving material therefore causing less damage. Flange Nuts are available with a plain flat underside of the flange or with a serrated underside for more grip upon tightening. The flange on these nuts also helps guard against loosening through vibration so nuts are less likely to work free. Available in A2, A4 and BZP Steel with some variants also boasting a Nyloc insert for locking purposes.