Code3 MicroCom™ 2 has a simple yet effective design. There are only 2 buttons and a turn knob. One button is for the air horn and the other button is to manually operate the siren. The turn knob allows you to switch between the different siren tones. This siren has 5 different tones: Wail, yelp, Hi-Lo, HyperYelp, and HyperLo. In order to use the HyperYelp and HyperLo the amplifier needs to installed, not included with the siren. There is no on/off switch, the siren turns on/off with the vehicle. The siren also turns off when the vehicle is put into park. With a remote input you can scroll through the different siren tones. When the PTT button on the microphone is pressed it over rides all siren tones. This siren has the ability to do radio rebroadcast and remote switching from steering wheel or another switch.