5/8"-18 Chrome Plated Steel Fine Thread Flat Head Acorn Cap NutsType: Cap Nuts
Head Style: Flat (15/16" Wrench)
Thread Size: 18 (Fine)
Shape: Flat Head Acorn
Type: Cap Nut
A closed nut having a dome-like cap over the back, protruding part of the engaged screw or bolt. Also called an acorn nut.