TPI (20 pcs) 1/2"-20 Premium Chrome Closed Bulge Acorn Wheel/Lug Nuts, B903542HT-20, 1.4" Tall, 13/16" / 21mm Hex Size Bulge closed acorn design, 1.4" Tall, 13/16" Hex, Cone Seat. 3 layers of brilliantly leveled Nickel undercoating followed by 1 reflective layer of chrome Greater seating surface to prevent damage during installation. Cold forged and heat-treated for Optimal Hardness. Precision Threads