Telex/ Electrovoice compact wireless transmitter receiver set freq 183.700 (still legal in US!) Originally used in police cars but can be adapted for other use You will need to add: 12VDC source for receiver 9v battery for bodypack 3.5mm lapel mic (2 conductor tip, sleeve electret type lapel or earset mic) Antenna -can use a piece of wire in BNC jack, or a BNC antenna easily found , or use BNC cable to remote it outside a vehicle. Amplifier and speaker There is a 9pin D9 plug but you can remove and use the screw terminals. Terminals, audio + ground (for audio and power) 12vdc + N.o. and common for remote power switch Good for tour bus, boat, parade float etc. Buyer to have proper knowledge of use and hookup NO lapel is included, (accepts standard 2 conductor lapel or earset mics. We can list one if you need!) No belt clip, see our listing for metal belt clip or use a cell phone holder! 10oz