The Telex WT-55 is designed for use with the Telex FMR-70 VHF wireless microphone system. The transmitter features a TA4 input that accommodates Telex and Electro-Voice lavalier and head-worn microphones. The WT-55 provides phantom power to the microphone output (5v Reg; 9v Unreg) and will remain powered for up to 9 hours on a single 9 Volt battery.