The Liberty Platinum with Two Wireless Receivers is the most popular, portable sound system on the market. This speaker is designed to provide crystal clear voice amplification, and is also great for music. It includes two wireless receivers. It has built-in rechargeable batteries, operates 6-8 hours on a full charge, and there is a battery charging LED bar indicator on the back. It also comes with two universal microphone jack inputs. Use it indoors/outdoors for schools, corporate events, sports, places of worship, and more!