The AdvanceTec Remote Speaker Microphone (RSM) is designed for use with the Push-to-Talk (PTT) Enabled handset on the Sprint® Network, providing amplified audio in transmission and reception through the remote speaker/microphone. It includes an independent control module with an internal rechargeable Lithium Ion battery which powers the RSM without any drain on the handset battery. <br /> <br />Amplified Audio <br />Clear Transmission and reception <br />Up to 21 days stand-by <br />Control Module with built-in belt clip <br />Supports ear piece for privacy or noisy environments <br />Internal rechargeable Lithium Ion battery <br />Charging LED <br />Will not drain phone battery
