Agonizer

From the Memory Alpha Information Directorate, a side project of Memory Alpha.

An agonizer was a small device worn on the belts of Imperial personnel, used to inflict pain for minor transgressions. More severe offenses called for using the agony booth. (MM)

The Terran Rebellion continued their brutal use. In 2372, Kira and Garak were subjected to these machines by their captors to make them more obedient. These agonizers were vastly improved over the older models, to point which they no longer needed physical contact with their victims to be effective. (SM)