WODWIN WIN-DM7w is 360 degree Omini-directional Conference Room Microphone. It with Bluetooth and wireless connection, easy plug and play. This Conference Speakerphone is buit in 4 microphone array with 2 extension mics for voice pick up range to 10 meters Suitable for people 10-15’s meeting room. Finely-tuned Hi-Fi speaker with explosion-proof sound treatment for treble. WIN-DM7W Conference Speakerphone is Built-in 3000mAh battery,that canlast up to10hours of conversation. Provide clear, smooth andstable audio and video experience. The USB conference mic is with dynamic noise reduction technology, enjoy clear and smooth video meeting.  So WIN-DM5B Conference Speaker is suitable for medium and large size conference room.