Ring of Clean Language (5e Equipment)
From D&D Wiki
This ring appears to be a ring made out of dark gray metal with elaborate designs etched into its surface. If you curse while wearing this ring, you experience a flash of pain. The flash of pain doesn't deal any damage. Alternatively, if you replace a curse word with something ridiculous, such as saying "Dag nabbit!" instead of "Damn it!", you experience a brief feeling of elation.