1.Can be used in cars, motorcycles, mopeds and many other kinds of vehicles, very practical. 2.100W Speaker gives very loud sound about 115 decibels at full volume . 3 Different sounds, can choose then by pressing the red buttons 4. Shout functions, authentic sound, suitable for some important occasions. 5. Press the left button in the sound selector then you can speaker what you want to say.Powered by 12V, easy to install and use. With a cilp and a doubled sided tape, can put the sound selector freely.