If you are looking for one voice amplifier specially for outdoors, then this model M800 is perfect for you. <br> <b><br>As a voice amplifier / Megaphone </b> <b><br>As a Bluetooth speaker / External speaker </b> <b><br>As a mobile power / power bank / portable chargers </b> <b><br>IPX4</b> <b><br>Dust-proof </b> <b><br>Shockproof</b> <br><br> <br>●Amplify your voice and save your throat <br>●Small and compact, this nifty little voice amplifier speaker offers good sound quality. <br>●The headset is adjustable and fits comfortably. <br>●There are slots to add little SIMcards and drives for music and more. <br>●Perfect for group events and presentations <br>●Compatible with all audio device to be a portable speaker. <br>●No worry no power to charger your devices in outdoors any more! <br><br> <b>Specification:</b> <br>Output Power: 18W <br>Battery Capacity: 3.7V, 4400mAh <br>Charging voltage: 5V, 1A <br>Charging Time: 3 ~ 5 hours <br>Working Time: 10 ~12 hours. (it depends on how do you use) <br><br> <b>Pacakge includes: </b> <br> 1*amplifier speaker/ 1*headset mic/ 1*waistband/ 1*charging cable/ 1*5V charger / 1*audio cable/ 1*manual