Pfeilverzahnung (Feminine)

double-helical gearing (Neuter)

double-helical teeth (Neuter)

herringbone gearing (Neuter)

herringbone teeth (Neuter)

diente de espiga (Neuter)

diente doble helicoidal (Neuter)

engranaje doble helicoidal (Neuter)

人字齿 (Neuter)