The Joker has a non-angled 12-point beak; therefore it requires just 30° of working space; otherwise it functions just like a regular open end wrench. The dark metal plate dual functions as a retainer; preventing the nut to slip through the wrench beak or it holds the nut. 30° further the metal retainer plate allows the nut to slide through; or grip it since the metal plate is equipped with a hardened ragged edge. The teeth of his edge will ''bite'' itself into a rounded-off nut; loosening it where others do nothing but slip-off. Color coded for size. Size: 22mm/24mm. Overall length: 260;5mm.