OvisLink headset amplifier, connect headset to different telephone brands and models. You can increase headset speaker or microphone volume as desire. For telephones that do not support headset function, you may use this amplifer to connect both the hand receiver and headset to the phone. The switch on the amplifer gives you choice to use hand receiver or headset.

This amplifer needs 2 AA battery to operate. And the batteries are not included in the package.