3/8"-16 18-8 Stainless Steel Coarse Thread High Crown Acorn Nuts (6 pcs.)

Diameter: 3/8"
Diameter 2: 5/8"
Thickness: 13/16"
Material: Stainless Steel
Driver Type: 9/16" Wrench
Thread Size: 16 (Coarse)
Shape: High Crown Acorn
Hardness: 18-8
Type: Cap Nut

Box of 6.

A closed nut having a dome-like cap over the back, protruding part of the engaged screw or bolt. Also called an acorn nut.