SRD:Helm of Telepathy
From D&D Wiki
|This material is published under the OGL 1.0a.|
Helm of Telepathy: The wearer can use detect thoughts at will. Furthermore, he can send a telepathic message to anyone whose surface thoughts he is reading (allowing two-way communication). Once per day, the wearer of the helm can implant a suggestion (as the spell, Will DC 14 negates) along with his telepathic message.