You can adjust the volume by sliding the volume regulator so that you get the attention of others when necessary. Loud and Powerful: This stylish portable amplifier is extremely lightweight and amplifies your voice loudly and clearly. And sturdy and portable, not easy to fade, pay attention to every detail, pursue perfect quality. Clear Sound and Long Distance: Hear up to 2000 meters away with this professional amplifier. Amplify your voice clearly. This megaphone speaker produces a powerful 75 watts of sound. Multiple functions: talk, speaker, record and play, volume control record playback, USB/SD memory card playback, built-in USB flash memory and SD memory card reader, built-in AUX input for connecting MP3 and similar devices. MULTIFUNCTIONAL APPLICATIONS: This compact large phone speaker is designed for indoor and outdoor use by tutors, cheerleaders, schools, sports teams, event organizers, etc. for various purposes.