Bulwark Dock Bumpers are easily installed, they are long lasting to protect dock equipment, building walls and truck cargo from potential damage.Bumper projection should be specified at not less than 4. For recessed docks or special applications, additional projection may be required.Installation Details:All laminated dock bumpers are assembled with two 3x 3x 14 thick steel angles. The angles are fastened with threaded rod and nut. All exposed metal parts are factory painted.We recommend all bumpers to be installed 1 to 2 below dock level.Use 34 or 58 expansion bolts with a minimum length of 3.