Listen Technologies TP-DX TalkPerfect Duplex Amplifier

The TalkPerfect Duplex Amplifier lets both sides of a conversation talk and hear each other at the same time through a glass or plastic screen, the kind of barrier found at a bank teller window, ticket booth, or pharmacy counter.

It replaces the strained, one-at-a-time shouting that a plain speaker grille forces on staff and customers alike.