... On/off key,volume contro Why choose Mobile Phone Transceiver?Hands Free, Retro style, radiation1) Talkback systems ... Long endurance. Only with 2*AAA batteries, transceiver can hold 15 hours constantly.4)A ... 5mmFeatures:1: Style and convenience: Use this awesome transceiver as a speaker! You can play music, pause ... music, you can also use the Tomko Transceiver as an alternative for talking on your phone ...