8-1/4" Tall Assorted Color Large Stainless or Rubber Bull Balls
Truck nuts - Wikipedia
Amazon.com: BULLS BALLS Truck Nuts, Solid Color-Blue 8" Tall Series, Made in USA : Automotive
A different kind of truck nuts : r/funny
Amazon.com: United Pacific 70144 8.25” Tall Large Low-Hanging Rubber Bull Balls, Injection Molded Rubber, Perfect for Trailer Hitches/Bumpers - Blue - One Unit : Automotive