Image Item No. Description  6628  Technic, Pin with Friction Ridges and Tow Ball (Undetermined Type) Catalog: Parts: Technic, Pin  6628  Technic, Pin with Friction Ridges and Tow Ball (Undetermined Type) Catalog: Parts: Technic, Pin  6628  Technic, Pin with Friction Ridges and Tow Ball (Undetermined Type) Catalog: Parts: Technic, Pin